TYLER, Texas—A traffic stop on Interstate 20 in the Tyler area yielded about 1,300 pounds of marijuana from the trailer of an 18-wheeler.

Smith County Sheriff J.B. Smith says the stop early Friday, leading to the discovery of $7 million worth of marijuana, involved an eastbound rig suspected of speeding.

Smith says the driver acted suspicious, so deputies asked to search the vehicle, which was bound for Georgia. The marijuana was discovered in stacked boxes, including some labeled “fragile.”

Officials believe the rig was traveling from Tucson, Ariz., to Atlanta.

Smith says the driver was detained for questioning.