The woman was in the 200 block of Mill Street when a white man with long, blond hair pulled a gun on her at about 1:15 p.m., said Prince William police spokesman Dennis Mangan.
Police did not say what the suspect stole.
The man fled in a dark vehicle and the woman gave a complete description of it to police, Mangan said.
The vehicle was identified moments later by Prince William police Chief Charlie T. Deane, who was in Lake Ridge near where the suspect parked — at 12206 Harbor Drive.
“Fortunately, the victim obtained a license number, our dispatcher broadcast that, and it came back to an address on Harbor Drive,” Deane said. “We responded there immediately. It was minutes after the vehicle returned from the scene.”
Additional units were called, including a K-9 unit, Mangan said.
A phone call was made to the house and police told the man to come out. Three men walked out of the home and one was subsequently arrested with no resistance, Deane said.
Police did not immediately release the suspect’s name or list the charges pending against him.
As of Tuesday afternoon, officers were attempting to get a search warrant for the firearm involved.