Topeka ? A man who authorities say hurriedly pulled off a highway to avoid a phony “drug check” was sentenced Monday to three years in federal prison for trafficking marijuana.

Zeferino Olivas Ortega, 31, of Odessa, Texas, was pulling a horse trailer along Interstate 35 in Lyon County in October when he saw a sign warning of a “drug check lane,” officials said.

Ortega changed lanes to avoid the drug check, but a Kansas Highway Patrol trooper pulled him over for failing to signal.

“The drug check lane was a ruse,” U.S. Atty. Eric Melgren said in a news release Tuesday. “Mr. Ortega’s reaction, however, was to violate traffic laws in his haste to avoid any contact with law enforcement.”

Highway Patrol troopers, alerted by a drug dog called to the scene, discovered 1,000 pounds of marijuana in a hidden compartment in the horse trailer, the U.S. attorney’s office said.

Ortega pleaded guilty in February to one count of possession with intent to distribute marijuana.