By Steve Beck

PHILADELPHIA (CBS) — Police are investigating the shooting death of a man in Northeast Philadelphia late Wednesday night.

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The incident happened at about 11 p.m. in the 6600 block of Castor Avenue in the city’s Oxford Circle section.

According to investigators, the victim was walking down the street after shopping when he was approached from behind by an unknown man.

The suspect shot the victim one time in the back of head and then ran from the scene.

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The victim was rushed to Aria Health Torresdale Hospital, but was later pronounced dead.

The suspect remains on the loose.

The incident remains under investigation.

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