Police believe the robber was assisted by individuals in a gray van.

By: KDKA’s Ross Guidotti

ROSTRAVER TOWNSHIP, Pa. (KDKA) — Police are investigating an armed robbery at a gas station in Westmoreland County.

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It was a normal night at the Marathon gas station on Route 51 in Rostraver on Monday. That is until about 9:20 p.m., when a man walked into the gas station.

Investigators tell KDKA that the gunman pulled a sawed-off shotgun out of a backpack on his chest and threatened to shoot the clerk. He also demanded cash.

With cash in hand, the suspect was gone in a flash.

(Photo Credit: KDKA)

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Police believe the robber was assisted by individuals in a gray van, possibly a silver Chrysler Pacifica, that pulled into the gas station just before the robbery.

“It appears there were three individuals in the van,” said Greg Resetar, the Rostraver police chief.

It’s believed that the van pulled around to the back of the gas station, waiting for the suspect to finish the job. Police believe the group did this in a few other places over the last 24 hours.

“There are some other robberies that are being investigated, not saying that they are connected, but there are some similarities with the clothing,” said Resetar.

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The suspect is described as a thin, Black man who is 5-foot-6. He was wearing a black hoodie with light blue jeans.