next Image 1 of 2

prev Image 2 of 2

A Mexican drug cartel recently used its painting skills to smuggle millions of dollars of marijuana into the United States, a brushstroke of genius of sorts until the effort was uncovered by a federal border agent.

U.S. Customs and Border Protection (CBP) agents stopped a suspicious tractor trailer late Thursday on Interstate 19, south of Tucson, Ariz. Inside, the driver said, was a shipment of watermelons. But when agents inspected the shipment using X-ray imaging, they discovered the purported fruit was actually packages of marijuana painted to look like watermelons.

"These criminals use a lot of unique ways to try to conceal their narcotics," Tucson CBP Agent Bryan Flowers said. "We've seen individuals use false compartments in the seats and gas tanks. We've also found marijuana in tractor trailers here before."

The truck had already crossed into the United States about 20 miles south, near Nogales. The trailer's contents were discovered at a second mobile checkpoint close to Tucson.

Drug Enforcement Administration officials later took custody of the contraband and tractor trailer, estimating the value of the marijuana in the millions.

Flowers said this isn't the first time the agency found marijuana disguised as fruit.

In April 2010, agents discovered 9,500 pounds hidden in a load of real watermelons. In June 2008 in Nogales a narcotics dog helped sniff out 5,000 pounds of pot valued at $8.3 million. DEA officials in Phoenix are still determining the street value and total weight of Thursday night's haul.

The driver of the truck remains in custody, authorities said.