27-year-old Sharif Wynn of Philadelphia was arrested in the 100 block of North Madison Street Thursday.
Wynn claims the shooting was accidental.
Police say Wynn was dating the victim's ex-girlfriend.
The shooting happened yesterday at 2:00 p.m. at a barbershop on Copley Road.
Police say the gunman walked up to the victim, who worked at the barbershop, and demanded money.
Authorities say though the worker gave the gunman money, he was then shot in the head.
Upper Darby Police Superintendent Michael Chitwood told Action News the barbershop worker appears to have been targeted.
Medics rushed the victim to Mercy Fitzgerald Hospital where he was pronounced dead a short time later.
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