An 81-year-old man who spent 15 years in prison for the 1972 slaying of Emanuel Gambino, the nephew of infamous mafia leader Carlo Gambino, has pleaded guilty to a felony drug charge in Wyoming.

​Henry Sentner of Myrtle Beach, South Carolina, pleaded guilty to possession with intent to deliver marijuana Friday in Laramie County District Court as part of a plea deal with prosecutors.

Sentner was arrested on Sept. 24 after a Cheyenne-area trooper pulled him over for speeding on Interstate 80 and discovered 35 pounds of marijuana in his rental car.

According to an affidavit, Sentner advised the trooper "he was on his way from California" and that "he does this run often."

In exchange for his plea, the state agreed to drop a felony possession of marijuana and speeding charge against Sentner. Prosecutors are seeking a sentence of four to six years in prison.