A 55-year-old Woodbridge man walking his dog was shot and killed in a robbery Wednesday night, and an off-duty Prince William County police officer captured a fleeing murder suspect, police said.

Twenty-five-year-old Aric Alexander Smith, of Woodbridge, was charged with first-degree murder, armed robbery and using a firearm in the commission of a felony.

Police said that the victim, George Lee Holley Sr. was taking his dog for a stroll in the 3700 block of Wertz Drive at about 9:40 p.m. Wednesday, when Smith approached him. During the encounter, Smith shot Holley and robbed him, police said.

Police Lt. Carlos Robles was working a second security job nearby when the call went out for a report of shots fired, police said. Witnesses reported seeing a man fleeing the area on foot, and Robles found a man that matched the description on Cardinal Drive. After a brief struggle, Robles was able to detain Smith.

Police said they recovered Holley's stolen property and the gun used in the shooting, which has been reported stolen from a vehicle last week in Montclair.