PHILADELPHIA (CBS) — A man has died after being shot in the back of the head late Monday night.

Police responded to a shooting inside a home on the 8300 block of Williams Avenue around 9:30pm.

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Upon arrival they found an unconscious 29-year-old man in the basement suffering from a gunshot wound to the head.

He was transported to the hospital in serious condition, and was pronounced dead around 11:00pm.

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There is no known motive for the shooting at this time, but several family members and neighbors in the time house at the time say they heard an argument, before the victim yelled for someone to call the police, followed by a gunshot.

No weapons were recovered from the scene and no one else was hurt.

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Detectives are continuing to investigate the shooting.