Federal agents in charge of monitoring drug smuggling along the U.S.-Mexico border say more and more teenagers are getting involved in the smuggling trade – and may even be at risk for recruitment.

According to federal agents, many suspected teen smugglers have been caught this year at the San Ysidro border trying to cross into the U.S. with drugs secretly taped to their bodies.

Agents say both American and Mexican children as young as 12 years old are being recruited by cartels as drug mules. And, these days, marijuana is no longer the drug of choice.

“It shocks me and saddens me that kids are getting involved. It doesn’t shock me that cartels will use whatever method they need,” said Jose Garcia, a deputy special agent for ICE Homeland Security Investigations.

Garcia says his agents have been focusing on teen drug smugglers since 2009.

So far, Garcia says cartels have recruited kids outside schools, arcades and malls from the South Bay to Poway, and as far east as Mountain Empire.

Social media has also been used to entice potential teen smugglers.

“We’ve even had one recruited by someone they know on Facebook,” said Garcia.

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The special agent says teens can carry as much as six kilos of drugs hidden under their clothing. The money they get if they make it across the border is minimal compared to the risk they take.

“The lowest (payment) is $50 and the highest we’ve heard is about $500. But the average is somewhere between $75 and $300,” explained Garcia.

The cartel recruiters tell the kids that because they are minors, they won’t get in serious trouble.

However, Garcia says that selling point is misleading.

“The truth is if they are arrested with narcotics, especially hard narcotics, they're going to have two felonies on their record,” said Garcia.

Last year, a record 190 teens – ages 18 and under – were caught smuggling drugs along the San Diego County-Mexico border, according to federal investigators.

So far this year, the number is down to 128, but Garcia says there are still disturbing new trends.

While marijuana was once the main drug being smuggled by teenagers, now it’s meth.

Also, recruiters used to target mainly teenage boys, but now they’re targeting young girls.

"If you look at the way that some females are dressed, it's hard to detect, they're wearing skinny jeans and tight tops and they still manage to hide it on them so the untrained eye wouldn't pick up on it," explained Garcia.

To help combat the teen drug smuggling trend, agents have formed a special outreach program that travels from school to school, warning kids about the dangers of drug smuggling.

Agents also warn parents to be alert and aware of their teens’ cash flow. Agents say that if a child suddenly has a lot of money and parent don’t know where it came from, it could be a red flag.