Ethan Miller / Getty Images file

Radio talk show host Bubba the Love Sponge, the performing name used by Todd Alan Clem, is shown attending the Adult Video News Awards Show on Jan. 12, 2008, in Las Vegas.

When a Florida shock jock threatened to "deep fat fry" a Quran earlier this year, Gen. John Allen, the commander of U.S. and NATO troops in Afghanistan, and CIA Director David Petraeus both reached out to Tampa socialite Jill Kelley to help tamp down what they saw as a potential threat to the safety of U.S. troops, according to emails released by the city of Tampa.

In the emails, Kelley -- indicating she was acting at the behest of the high level U.S. government officials -- asked Tampa Mayor Bob Buckhorn to intervene and get the radio disc jockey to stand down.

"I have Petraeus & Allen both emailing me about getting this dealt with," Kelley wrote to Buckhorn in a March 7 email. The day before, Kelley mentioned similar requests to Buckhorn from both Allen and Vice Adm. Robert Harward, deputy commander of the U.S. Central Command in Tampa. "I just got off the phone with Gen. Allen & Adm Harward," she wrote. "I'm going to need your assistance, vice versa with the potential crises we'll be dealing with."

The emails offer a new glimpse at Kelley's relations with top  U.S. military officials -- as well as Petraeus, who had by then left the military to take the helm at the CIA -- shortly before she went to an FBI agent to complain about anonymous harassing emails she was receiving. The resulting FBI probe into what was initially viewed as a potential case of "cyber-stalking" led to Petraeus’ resignation as CIA director and triggered a separate investigation by the Pentagon inspector general into what has been described as "potentially inappropriate" email correspondence between Allen and Kelley.

Numerous government and law enforcement officials have told NBC News that the FBI investigation revealed that Petraeus' biographer, Paula Broadwell, had sent the threatening emails and that agents subsequently uncovered evidence that she had an extramarital affair with Petraeus.

Newer emails to Buckhorn also show Kelley's anxiety as the scandal broke last week and the media descended on her home.

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Jill Kelley leaves her Tampa, Fla., home on Tuesday.

"Can you help out with obstruction by the paparazzi, since they're blocking our driveway, and continue to trespass on my property," she wrote Buckhorn on Tuesday. "My kids are scared and need their 'home' back."

In other emails to Buckhorn, Kelley referred to numerous social events with generals from Central Command – and referred repeatedly to Petraeus and others. One also described a post-election visit to the White House, just before the scandal broke.

"ps I'll be in DC this weekend with Petraeus, but let's set up a double date when I return!" she wrote to Buckhorn on Oct. 9, 2011. The next day, she added, "I'll be sure to send the Director your regards --should be another fabulous weekend in DC."

On Nov. 24, 2011, she wrote: "We just got back from spending the weekend with the Petraeus (it was Dave's 59th Birthday) and he said to send you his best! :) "

On Jan. 13 of this year, she wrote to an aide to Buckhorn: “I’m up in DC having dinner tonight with Gen. Petraeus and Gen. John Allen (he replaced Petraeus as the Commander in Afghanistan.)”

The email correspondence included an effusive account of a dinner with the king of Jordan, Abdullah II bin Al-Hussein. “The King and his sister (the Princess) are awesome people!” Kelley wrote to the mayor on May 16, 2011.

Kelley also sent a formal invitation to a party in her honor at the U.S. Central Command  on April 19 -- forwarded by Centcom's chief of protocol.

 "Vice Admiral Robert S. Harward, Deputy Commander, United States Central Command request the pleasure of your company at a ceremony in honor of Mrs. Jill Kelley," the invitation reads in part.

 A military source said the party honoring Kelley was to formally give her the title of "Honorary Ambassador to the Coalition" -- a certificate given to private citizens who are "friends" of the base. Kelley used the title in her later email correspondence: "Today, I will be hosting a group of VIPs visiting from Afghanistan Pakistan Nepal, here by the authority of the State Department," she wrote Buckhorn on May 14. "As the Ambassador to the Coalition, I will taking them to Centcom with the great assistance of Gen. Mattis & Adm Harward." (Marine Gen. James Mattis is the commander of U.S. Central Command at MacDill Air Force Base.)

Broadwell, Kelley both were repeat White House visitors, official says

Kelley’s access to the military elite continued right up to this month. On Nov. 8 — just a day before Petraeus resigned as CIA director -- she emailed Buckhorn: “I was at the WH with my friends in the Administration this weekend—the stress was surreal! But glad POTUS has been re-elected!”

Kelley's emails referring to the comments about burning the Quran by the Tampa shock jock, known as "Bubba the Love Sponge Clem," reflected a genuine concern among U.S. military officials that they would endanger U.S. troops, a U.S. military official told NBC News. At the time, there were riots and deaths in Afghanistan over the burning of Qurans by U.S. soldiers.

 "It was absolutely a concern," Lt. Col. T.G. Taylor, CentCom spokesman, said in an interview. Taylor said he personally called the disc jockey and told him, "Look Bubba, somebody's going to get hurt if you do this." He was "completely reasonable and said he understood," Taylor added.

Buckhorn, the Tampa mayor, told Kelley when she emailed about the issue that the city's police chief was handling the matter, but added: "This Bubba the Love Sponge is a complete moron." 

For his part, the disc jockey told the Tampa Bay Times that he abandoned his plans to “deep fat fry” a copy of the Quran, the Muslim holy book, at the request of local law enforcement and credited Kelley’s role: “Probably she did get Intel to have me stop it, and that’s the problem itself,” he said. 

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Jill Kelley and Paula Broadwell, the two women at the center of the David Petraeus scandal, both visited the White House multiple times during the last four years. 

Kelley  has visited three times since September of this year, and Broadwell’s two visits were in 2009 and 2011,  a White House official told NBC News on Friday, speaking on condition of anonymity. 

Kelley’s trips were set up by a White House staffer she met at MacDill Air Force Base in Tampa, Fla., where she served as an unpaid social coordinator.

The staffer hosted Kelley and her twin sister, Natalie Khawam, for breakfast in the White House cafeteria, known as the mess, on Sept. 28 and again, for lunch, on Oct. 24. 

The third visit, on Sunday, Nov. 4, occurred just three days before Gen. Petraeus resigned as CIA director, citing an extramarital affair.  Kelley also took a tour of the White House that day with her husband, Scott, and their three children, as well as Khawam and her child. 

Broadwell visited the White House twice -- in June 2009, when she met with a National Security Staff member who handled Afghanistan and Pakistan policy, and in June 2011 when she attended a broad briefing on Afghanistan-Pakistan for approximately 20 guests, according to the White House official. 

The women have emerged as key figures in the scandal that cost Petraeus his job.

Numerous government and law enforcement officials have told NBC News that Kelley inadvertently triggered the investigation that revealed Petraeus' extramarital affair with Broadwell, his biographer, by complaining to an FBI agent she knew about a series of harassing emails she had received. Agents investigating the cyber-harassment case first determined that Broadwell was the author of the emails, then found evidence of her affair with Petraeus, the officials said.

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Then-CIA Director David Petraeus and Gen. John Allen, commander of  U.S. and NATO troops in Afghanistan, intervened in a Washington, D.C., custody battle in September, writing letters on behalf of a woman who was found by a judge to have "severe personal deficits in the areas of honesty and integrity."

The woman, Natalie Khawam, is the twin sister of Tampa socialite Jill Kelley, who has emerged as a central figure in the scandal that led to Petraeus’ resignation last week.

The letters, which have been obtained by NBC News, were filed in court on behalf of Khawam, who the judge hearing the case harshly criticized for a “stunning willingness to say anything, even under oath, to advance her own interests.”

At the time, Khawam was seeking to relax a judge's order restricting her visits with her now 4-year-old son. Holly Petraeus, the wife of the ex-CIA director previously signed an affidavit in support of Khawam, according to the lawyer for Grayson Wolfe, Khawam's ex-husband. The letters were first reported by the New York Post.

Chip Somodevilla / Getty Images file

Gen. John Allen, right, commander of U.S. and NATO forces in Afghanistan, and former CIA Director David Petraeus appear ath the White House on April 28, 2011.

The letters came to light after Kelley emerged as a key player in the scandal surrounding emails that officials say were written by Petraeus biographer Paula Broadwell – a trail of correspondence that led to Petraeus’ resignation as CIA director and a Pentagon investigation of Allen over what defense officials have described as “potentially inappropriate” emails he exchanged with Kelley.

The legal battle between Khawam and Wolfe has been bitter, according to court records. Both sides have accused one another of repeatedly lying to the court -- including about invitations to events involving prominent members of Congress.

The court records also shed some light on the lifestyle of the Kelley family: At one point, the judge -- who had directed Kelley's sister to pay child support and the legal fees of her ex-husband -- noted that Khawam lived "rent-free in Florida with her sister" in a home described as a "ten bedroom mansion in a beautiful neighborhood right on Tampa Bay."

The judge also ruled that Jill Kelley was a "patently biased and unbelievable witness" when she testified about an alleged case of domestic abuse by her twin sister's ex-husband.

In a Nov. 9, 2011, ruling, D.C. Superior Court Judge Neal E. Kravitz dismissed Kelley's testimony that she saw Wolfe push Khawam down a flight of stairs inside the Kelleys’ home. Kelley testified that her sister was holding the couple's baby in one hand and "somehow was able to stand her ground on the staircase" as Wolfe, "who is substantially larger and stronger ... pushed Ms. Khawam from above with both hands and all of his might."

Read David Petraeus' letter to the court

Read Gen. John Allen's letter to the court

"The court does not credit this testimony," Kravitz wrote, after calling Kelley an "unbelievable witness." He called it "part of an ever-expanding set of sensational accusations against Mr. Wolfe that are so numerous, so extraordinary and ... so distorted that they defy any common sense view of reality."

Amy Scherzer / Tampa Bay Times via Zuma Press

Natalie Khawam, twin sister of Jill Kelley.

Petraeus and Allen entered the case two months ago, penning separate letters attesting to Khawam’s parenting.

"My wife and I have known Natalie for approximately three years, getting to know her while serving in Tampa, Florida, through her friendship with Dr. and Mrs. Scott Kelley," Petraeus wrote in his letter dated Sept. 20, identifying himself under his signature as "General, U.S. Army (Retired.) "

He added that he has observed Khawam with her son on many occasions, "including when we hosted them and the Kelley family for Christmas dinner this past year." It was "clear to me," he added, that Natalie's son "would benefit from much more time with his Mother and from removal of the burdensome restrictions imposed on her."

Allen's letter, dated Sept. 22, which identified him under his signature as "General, United States Marine Corps," is similar. It stated that he had gotten to know Khawam while serving at the U.S. Central Command in Florida and observed her with her son "on multiple occasions" at "command social functions."

"In light of Natalie's maturity, integrity and steadfast commitment to raising her child, I humbly request your reconsideration of the existing mandated custody settlement," the letter concluded.

Defense official fires back, denies Afghanistan commander exchanged 'inappropriate' emails

A source familiar with Kelley’s views said Tuesday night that both Petraeus and Allen have been friends of Kelley and her sister Khawam for years. The source added:  “When you're involved in a custody issue, you want letters of support. There is nothing unusual about that.” 

Sandra Wilkof, the lawyer for ex-husband Wolfe, said the letters from both high ranking military men misstated the facts of the case. Both letters asked the court to change the terms of a "court settlement" between the couple. In fact, Wilkof, said, "There was no court settlement. There was a court order," she said, awarding custody to Wolfe and supervised visits for Khawam.

Slideshow: Petraeus case: Cast of characters

ISAF via Reuters file

Meet the people who have been pulled into the scandal that caused Gen. David Petraeus to resign.

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Judge Kravitz has not given Wolfe a free pass. He wrote in the Nov. 9, 2011 ruling that Wolfe "does not possess an entirely healthy psychological make-up.” And he noted that Wolfe had taken “questionable deductions” on his tax returns and “may have been less than fully candid in his testimony about contacts he may have had with the FriendFinder online dating service.”

But he has saved his harshest words for Khawam, writing that “Mr. Wolfe … is much more honest than Ms. Khawam, and he conducts himself with far greater integrity.”

In the ruling, he found that Khawam had taken the couple's son to Florida when he was only four months old  and refused to tell Wolfe of his whereabouts, ignored court orders to allow visits with his father,  changed the boy's first name without his father's knowledge  and made unfounded claims of abuse against her ex-husband.  

"The evidence established that Ms. Khawam has extreme personal deficits in the areas of  honesty and integrity," Kravitz wrote. "Ms. Khawam's false domestic violence petitions (and her equally false testimony at trial relating to many of the same allegations) are merely the most stunning examples of Ms. Khawam's willingness to say anything, even under oath, to advance her own personal interests at the expense of Mr. Wolfe, the child, and others."

Khawam's lawyer, Greg Jacob, with the law firm of O'Melveny & Myers, did not respond to requests for comment.

In the latest wrinkle in the case, Wolfe's lawyer filed a motion on Oct. 26 opposing the efforts of Khawam to modify the visitation schedule, saying that neither of the letters by Petraeus and Allen promised “corroborating testimony” relevant to the court's determination.

The motion also argued that Khawam had misrepresented social events she had asked the court to let her attend with her son. In one case, Wolfe's motion stated, Khawam had asked the court to let her take her son to a "family clambake" at "the personal invitation" of Rhode Island Sen. Sheldon Whitehouse. In fact, the motion states, this was "nothing more than a … political fundraising event."

On other occasions, the motion states, Khawam had sought to take her son to events with "Senator Kerry" and the baptism of "former Congressman Patrick Kennedy's child" in New Jersey. In fact, the motion states, the invitation to be with Sen. John Kerry was a Democratic Senatorial Campaign Committee event in Martha's Vineyard and that he denied her request to take the boy to those events because he did not believe it was in "the child's best interests."

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A June 23, 2011, file photo shows Paula Broadwell, second from left, watching as Gen. David Petraeus and his wife, Holly Petraeus arrive for a Senate Select Intelligence Committee hearing on Petraeus' nomination to be director of the Central Intelligence Agency.

What began with David Petraeus’ surprise resignation as CIA director on Friday resulting from an extramarital affair has now spiraled into a complicated story of infidelity, intrigue and politics.

Petraeus’ admission of an extramarital affair quickly led to his biographer, Paula Broadwell, and an examination of her relationship with the decorated war hero. The length of the FBI’s investigation of “menacing” emails sent to Petraeus’ family friend Jill Kelley, and the timing of the announcement of his departure from the Obama administration fueled conspiracy theories. Then Gen. John Allen, Petraeus’ successor as military commander in Afghanistan, was embroiled in the scandal, accused by U.S. officials of sending “inappropriate” emails to Kelley.

To help you keep the facts straight, NBC News has compiled this timeline, based on reporting by NBC News and other published accounts:

Spring 2006 -- Paula Broadwell meets Gen. David Petraeus, when she introduces herself after he gave a speech at Harvard's Kennedy School, where Broadwell was working on a master's degree, the Wall Street Journal reported. 

October 2008 -- Petraeus takes over as head of U.S. Central Command, based at MacDill Air Force Base. While serving there, he reportedly meets Jill Kelley and her husband, Dr. Scott Kelley. She is described in various accounts as a volunteer “social liaison” between the community and the base.

2008 -- Broadwell begins her doctoral dissertation, "a case study of General Petraeus’ leadership," according to Rolling Stone magazine.  

June 2009 -- Broadwell and her husband, Scott, purchase a home in Charlotte, N.C., the Charlotte Observer reports. 

June 2010 -- Petraeus is named as replacement for Gen. Stanley McChrystal as the top commander in Afghanistan after the latter makes impolitic remarks to a Rolling Stone reporter. Broadwell decides to turn her dissertation into a book.  

July 2010-July 2011 – According to an online biography of Broadwell that was taken down after Petraeus’ resignation, she made multiple trips to Afghanistan during this period, where she “embedded with the general, his headquarters staff and his soldiers on the front lines of fighting across Afghanistan to chronicle the experiences of this American general as they are brought to bear in the terrible crucible of war.”  

Aug. 31, 2011 -- Petraeus retires from the U.S. Army, departs Afghanistan.

Sept. 6, 2011 -- Petraeus takes over as director of the CIA.

Early November 2011 – According to former Petraeus spokesman Steve Boylan, who had spoken to his former boss after his resignation, Petraeus' affair with  Broadwell began around this time, approximately two months after he took the CIA job.  

January 2012 – “All In, The Education of General David Petraeus,” by Paula Broadwell with Vernon Loeb is published by Penguin Press.

May 2012 – “Menacing” emails – five to 10 of them, according to the Wall Street Journal -- began arriving in Jill Kelley's inbox, NBC’s Michael Isikoff and Pete Williams report. 

Emails on 'comings and goings' of Petraeus, other military officials escalated FBI concerns

June 2012 – The FBI investigation begins. A source close to Kelley tells Isikoff that she took the emails, which she viewed as harassing or menacing, to the FBI. The source said the anonymous emails didn’t mention Petraeus by name, but subsequent emails – sent from multiple alias accounts -- contained references to the "comings and goings" of high-level military officials -- including events that were not on any public schedule. This raised the question as to whether somebody had access to sensitive -- and classified -- information about the CIA director. 

T.Ortega Gaines / Charlotte Observer via Reuters

Paula Broadwell is pictured before embarking on a national book tour to promote "All In," her biography of Gen. David Petraeus.

July 2012 – Approximate end of the affair between Broadwell and Petraeus, according to former Petraeus spokesman Steve Boylan, who  tells NBC’s Kristen Welker in early November that it ended “about four months ago.” 

Late  summer -- Attorney General Eric Holder is told that agents have discovered an email link between Petraeus and Broadwell, which included exchange of “explicit details of a sexual nature,” according to the Wall Street Journal. 

September – FBI agents interview Paula Broadwell for first time, NBC’s Pete Williams reports.

Oct. 27  -- House Majority Leader Eric Cantor speaks to an FBI agent who had worked on the Petraeus investigation, according to Cantor spokesman Doug Heye. The agent-- who had originally contacted Rep. Dave Reichert, a Republican from Washington -- raised concerns that "sensitive information" relating to Petraeus may have been "compromised," Heye said. The timing of the tip to Reichert is not clear.

Week of Oct. 29 – FBI agents interview Petraeus and Broadwell (for a second time), according to NBC’s Michael Isikoff.

Approximately Oct. 30-31 – Somewhere around this time frame, Petraeus traveled to Tripoli to conduct his own personal inquiry into Benghazi, according to author Bob Woodward, appearing on "Meet the Press" on Nov. 11. NBC’s Andrea Mitchell confirmed that Petraeus had recently traveled to Libya.

Oct. 31 – After conferring with his chief of staff, Steve Stombres, and Richard Cullen, a former attorney general of Virginia, Cantor had Stombres call the FBI chief of staff to relay the information he had received from the FBI agent, NBC News has reported.

Nov. 1 -- Cantor aide Steve Stombres is told by the FBI that it cannot confirm or deny an investigation, but the bureau official assured the leader's office it was acting to protect national security.

Nov. 2 – The FBI concludes its investigation, according to NBC News’ Michael Isikoff, citing senior U.S. law enforcement official; the  last FBI interviews with both Broadwell and Petraeus also took place this day, NBC’s  Pete Williams reports, citing federal officials.

Nov. 6 – Justice Department informs Director of National Intelligence James Clapper.

Nov. 7 – Clapper informs the White House.

Nov. 8 –  Petraeus calls White House Deputy Chief of Staff Thomas Donilon and asks to see the president, NBC’s Andrea Mitchell reports. The White House tells Obama of the FBI investigation of Petraeus and his admission of an extramarital affair.

Nov. 9 – Obama accepts Petraeus’ resignation; Senate and House leaders first learn of it from media calls. They then speak to Petraeus, but don’t hear directly from the president, Mitchell reported.

Nov. 11 – Jill Kelley and her husband, Scott, issue statement: "We and our family have been friends with Gen. Petraeus and his family for over five years. We respect his and his family's privacy and want the same for us and our three children."

Afghanistan military commander Gen. John Allen investigated for 'inappropriate' emails

Chuck Burton / AP

FBI agents carry boxes and a computer from the home of Paula Broadwell in Charlotte, N.C.

Nov. 12 – In a surprise statement during a trip to Australia, Defense Secretary Leon Panetta announces that U.S. General John Allen, who succeeded Petraeus as military commander in Afghanistan, is under investigation over allegations he exchanged “inappropriate” emails with Kelley, the woman who triggered the investigation of Petraeus. Meanwhile, FBI agents carry out a four-hour “consensual search” of Broadwell’s home in Charlotte, N.C., leaving with eight to 10 cardboard boxes.

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New in this version: FBI search Paula Broadwell's home Monday night; officials say the FBI agent who worked with Jill Kelley, the Tampa, Fla. woman who received anonymous emails from Broadwell, was dismissed from case because he became obsessed with Kelley.

Updated at 11:36 p.m. ET: “Menacing” anonymous emails that launched the FBI investigation which ultimately brought down CIA Director David Petraeus contained references to the “comings and goings” of high-level U.S. military officials, raising concerns that someone had improperly gained access to sensitive and classified information, a source close to the recipient tells NBC News.

The first email sent anonymously to Jill Kelley, the Tampa, Fla., woman who reported the threatening emails to the FBI, in May referred to Kelley socializing with other generals in the Tampa area and suggested it was inappropriate and should stop, according to the source close to Kelley, who spoke with NBC News on condition of anonymity.

After Kelley alerted the FBI, agents began pursuing it as a possible case of cyber harassment or stalking. "The thought was she was being followed," the source said.

The anonymous emails continued -- sent from multiple alias accounts -- and some later ones in the sequence contained references to Petraeus, though not by name, the source said.

What most alarmed Kelley and the FBI, the source said, were references to "the comings and goings" of high-level generals from the U.S. Central Command, which is based at MacDill Air Force Base in Tampa, and the U.S. Southern Command, as well as Petraeus -- including events that were not on any public schedule. This raised the question as to whether somebody had access to sensitive -- and classified -- information.

Moreover, the sender of the emails had "covered her tracks pretty well," the source said.

Multiple government and law enforcement officials have told NBC News that FBI agents traced the emails to Paula Broadwell, Petraeus’ biographer. In the course of the investigation, the agents also discovered emails between Petraeus and Broadwell that were indicative of an extramarital affair, they said.

The source close to Kelley said that she had never met Broadwell and had no idea who she was. The source also stressed that Kelley has been active in multiple social events in the Tampa area and is purely a social friend of the Petraeus family.

Meanwhile, it has come to light that the FBI agent contacted by Kelley about the emails she received from Broadwell was removed from the case. According to officials, the agent’s supervisors said he had become infatuated with Kelley and had sent her shirtless photos of himself.

The FBI remains involved in the case, however. On Monday evening, plain-clothed FBI agents arrived at Broadwell’s home in Dilworth, N.C. around 9 p.m. Monday night for what a senior law enforcement official called a “consensual search.” The official said the search is not a raid and “not a game changer.”

Rather, the official said that the FBI is being thorough as it finishes its investigation into Broadwell and whether she violated cyber-stalking or cyber-bullying laws.

The investigation of Petraeus has concluded. Law enforcement sources tell NBC News that Petraeus is not under investigation and that they don't expect their inquiry will result in criminal charges.

The search of Broadwell's home is not expected to yield information that would lead to charges against her, the official said. At the house, agents did not respond when reporters asked for their affiliation, although WCNC in Charlotte, N.C. confirmed they were with the FBI.

NBC News has been unable to reach Broadwell for comment.

The new information offers clues about how federal investigators could connect a handful of anonymous emails to Broadwell, a trained intelligence officer who spent years working with some of the most secretive agencies in the world.

Federal officials who spoke with NBC News on condition of anonymity on Monday said it took agents a while to figure out the source. They did that by finding out where the messages were sent from -- which cities, which Wi-Fi locations in hotels. That gave them names, which they then checked against guest lists from other cities and hotels, looking for common names. 

That led them to Broadwell, they said, noting that the pattern coincided with her travel to promote her book.

Finding the location from which the emails emanated would not have been difficult, experts say.

Some webmail services, including Yahoo and Microsoft's Outlook.com, send user IP addresses across the Web with every note, according to privacy researcher Chris Soghoian, a senior policy analyst at the American Civil Liberties Union. Those IP addresses can be used to track the physical location of a computer user connected to the Internet, sometimes without the help of an Internet service provider.

Broadwell had used a Yahoo account publicly in the past. If she used a new, fake Yahoo account for some of those anonymous emails, agents would have had an easy time gathering a list of IP addresses from the threatening emails Kelley provided to them. And even if she had used Gmail or another service that doesn't "leak" IP information, an FBI agent could have obtained such information by calling Google with a subpoena, the experts said.

Slideshow: Petraeus case: Cast of characters

ISAF via Reuters file

Meet the people who have been pulled into the scandal that caused Gen. David Petraeus to resign.

Launch slideshow

Once there was evidence to link Broadwell to the emails, agents would have had little trouble proving probable cause and getting a warrant under the provisions of the Stored Communications Act, which would allow them to access any emails sent or received during the prior 180 days. Agents could also have sought a wiretap order and monitored Broadwell’s email in real time, though wiretaps are more challenging to obtain, and there is no indication that agents took that step.

Soghoian said the successful cyberhunt for Broadwell shows anonymity is much harder to preserve than many Internet users realize.

"We see this again and again. We saw it with the Anonymous (hacker) arrests last year.  The lesson for the rest of us here us you have to go through a lot of steps to maintain anonymity, and you only have to screw up once," said Soghoian. "The FBI was able to pierce the veil of anonymity even for someone who's been trained. The government only has to get one clue. You have to be successful 100 percent of the time (when trying to hide)."

NBC News Justice correspondent Pete Williams contributed to this report.

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