Police are asking the public's help to identify a gunman who shot a security guard in the neck last week at a West Philadelphia gas station.

The victim was inside the Sunoco A-Plus gas station on Girard Avenue near 38th Street at 11:15 p.m. on Dec. 15 when he overheard a "disturbance" and decided to intervene, according to police. The guard did not work for Sunoco; rather, he was a customer, police said. The guard confronted the unruly man causing the disturbance, and the man left the station. But he returned within minutes and pointed a gun at the guard, police said. When the guard tried to leave the store, the gunman shot him in the back of the neck. He then rifled through the victim's pockets and stole his cell phone, police said. The guard was treated at the Hospital at the University of Pennsylvania and is recovering.

The gunman was seen fleeing in a green Chevy Venture minivan that had been parked at a gas pump. He's described as a black man, age 35 to 45, 5-foot-9 to 5-foot-11, 170 pounds, with a mustache and medium complexion. He was wearing a blue Polo hat, blue hooded jacket, blue jeans and white sneakers. Tipsters should call Southwest Detectives at (215) 686-3183 or -3184. See the video featuring the gunman here.