Philadelphia police say the 34-year-old man fatally shot while walking his dogs in West Philadelphia on Wednesday night was killed as a result of an argument.

Mark Marshall was walking his two chihuahuas about 7:45 p.m. on the 4600 block of Kingsessing Avenue - just a block away from his home - when he and another man began to argue, police said.

Police said the man pulled out a handgun and shot Marshall several times.

Marshall was taken to Penn Presbyterian Hospital, where he was pronounced dead about 15 minutes later.

On Wednesday night, police described the shooter as a man in a gray hooded sweatshirt and an orange hat. After the shooting, they said, he got into the passenger seat of a silver minivan that fled the scene.

No arrests have been made. Anyone with information on the case is asked to call the homicide unit at 215-686-3334.