A new warning has been issued at the country's ports of entry.
The Department of Homeland Security said drug smugglers are planting their drugs on unsuspecting drivers.
Agents began investigating this trend last summer to see if it was a threat. Now DHS tells NBC 7 the trend is growing and that border-crossers who specifically use the Sentri pass need to be aware.
“You have somebody who is completely unaware that there’s something attached to their vehicle and they’re going to get processed a little quicker because that’s part of that program -- your wait time won’t be as long," said Deputy Special Agent Joe Garcia with the Department of Homeland Security’s Investigations Unit.
Garcia says Sentri users are also targeted since they can usually avoid inspection.
The tactic involves using heavy duty magnets to attach bundles of drugs underneath vehicles and GPS trackers to monitor the driver's whereabouts.
"If you're part of this program it really is incumbent upon you to make sure that you know you secure your vehicle in a place that's safe," Garcia said. "If you're living in Mexico and crossing everyday you may want to take a look underneath your car on a daily basis."
Smugglers have attempted to pass bundles of cocaine and methamphetamine underneath these vehicles.
But now we are told they are mainly focusing on marijuana. Agents say the latest attempt was just last month.
Anyone with information regarding magnet-mounted drug smuggling activity or any type of drug smuggling can contact the DHS Tip Line at 1-866-347-2423 (from the United States), or 011-883-347-7242 (from Mexico). You can also submit online tips by clicking here.
Diana Guevara covers stories involving San Diego's Latino community. Send her your thoughts via Twitter @nbcsandiego or add your comment to our Facebook page.
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