CHESTER, Pa. — A man has been convicted of first-degree murder in the robbery and murder of a man found shot to death in a suburban Philadelphia gas station last year.

A Delaware County judge also convicted 20-year-old Leyron Johns on Friday of robbery and possession of an instrument of crime in the July 2015 death of 27-year-old Joseph Torres but acquitted him of a drug conspiracy charge.

Prosecutors said the West Chester father went to Chester to buy pills and was robbed and killed. A co-defendant last month pleaded guilty to third-degree murder and testified against Johns in a nonjury trial last week.

Defense attorney William Wismer argued that the plan was to scam the victim rather than rob him, and he took issue with the testimony of the other man.