Castle Shannon Police say an investigation is ongoing.

By: KDKA-TV News Staff

CASTLE SHANNON (KDKA) — Police are investigating after a stabbing late Friday night at a 7 Eleven/Sunoco in Castle Shannon.

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Castle Shannon Police say 3 employees at the Eleven/Sunoco gas station on Mt Lebanon Boulevard called to report an assault around 7:30 p.m. last night.

An argument between a patron and employee escalated, according to police, leading to the patron allegedly stabbing the clerk in the arm.

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The clerk is in stable condition.

The patron is thought to have fled the gas station on foot.

Police say witnesses described the patron as being around 5 feet tall and dressed in all black, with a beanie cap and face mask.

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They ask anyone with any information about the suspect’s whereabouts or the incident itself to contact them at 412-473-3056 or 911.