HILLSVILLE, Va. — Carroll County officers were able to arrest three Hispanic men on felony marijuana charges despite their using a “high-tech” method to smuggle the drug, Sheriff Warren Manning said Wednesday.

More than 300 pounds of marijuana valued at three-quarters of a million dollars — carefully concealed between insulation in panels of aluminum found in a tractor-trailer — were seized as a result of the Tuesday incident in Fancy Gap, Manning said.

The Carroll sheriff said the drug shipment is believed to have come directly from Mexico, based on recent trends in which lax immigration law enforcement and poverty conditions are fueling a steady stream of marijuana, cocaine and methamphetamine across the border.

Tuesday’s bust represented the fourth major drug arrest in the Surry-Carroll area within the past month involving either marijuana or cocaine.

Ironically, it occurred while Carroll County officers were investigating a theft-related case in the Fancy Gap community.

Deputies Donnie Spangler, Charles Catron and Bobby Melton had responded to the Kangaroo Express on State Road 148 about 2:30 a.m. to check on a tractor-trailer parked in a lot there. The rig came into question due to a rash of convenience store break-ins along interstates 77 and 81 in which the suspect is thought to have been driving a similar vehicle.

After speaking with the operator of the truck encountered Tuesday, officers checked the trailer and found two men inside.

Trooper David Barker of the Virginia State Police responded to the scene with a narcotics dog, which indicated the presence of drugs on both the road tractor and trailer. That led to the obtaining of a search warrant through efforts of 1st Sgt. Pat Harner and Sgt. Freddie Bobbitt of the Sheriff’s office.

The tractor-trailer then was taken to another location for unloading, and the narcotics dog focused on panels of aluminum with about 4 inches of Styrofoam between each section. After the panels were cut open, 28 packages of marijuana weighing from about 5 to 14 pounds were discovered.

Manning said the seized drugs have a street value of about $750,000.

“They were high-teching it,” the sheriff added of the method the three were using to conceal the drugs, making it appear that the rig simply was loaded with produce. He credited “good police work” on the part of the deputies for the marijuana find.

The rig’s driver, Mario Martinez, 30, of Whittier, Calif., was charged with possession with intent to distribute more than 5 pounds of marijuana and transporting illegal narcotics into the Commonwealth of Virginia.

The other two suspects, Ramon Sanchez Santago, 42, of Oregon, and Ramro Esparza Ibanez, 30, whose address was unavailable, were charged with possession with intent to distribute more than 5 pounds of marijuana and breaking and entering of a motor vehicle.

All three men are being held without privilege of bond in the New River Valley Regional Jail in Dublin. They are scheduled to appear in Carroll County General District Court Friday for advisement of counsel.

Contact Tom Joyce at tjoyce@mtairynews.com or at 719-1924.