By Tim Jimenez

PHILADELPHIA (CBS) – There has been an arrest in the death of a Mount Airy man who was discovered in an overturned SUV with a gunshot wound to his head Tuesday.

Philadelphia homicide investigators say Martina Wescott had been arguing with her boyfriend, 33-year-old Terrell Bruce. They were in a Ford Expedition, with Bruce behind the wheel.

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That’s when police say Wescott shot him. The SUV then crashed into a Subaru.

Martina Westcott

This happened on the 500 block of West Walnut Lane in Germantown around 12:30 p.m.

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When police and medics arrived, it appeared to just be a bad crash. But medics saw that Bruce had a gunshot wound to his head.

Witnesses told police that a woman got out of the Expedition and ran across the Walnut Lane Bridge.

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Police later arrested Wescott. Authorities say she’s facing murder and gun charges.