Kione Gary, 23, is being held without bail, according to court records.
Gary originally told authorities he was home with his girlfriend when her sisters and two men entered the 7901 Henry Ave. apartment and "approached him in a threatening manner."
Gary said he fired one shot at them before fleeing off the balcony, according to police.
Investigators now believe he was involved in a "domestic altercation" with his girlfriend that "escalated physically." His girlfriend called her mother and sisters who arrived at the apartment with 18-year-old Elijah Deloach and another man, PPD said.
Police said Gary shot Deloach in the chest just after he walked into the home. Deloach, of Elkins Park, was taken to Roxborough Hospital where he died just after midnight, officials said.
"There was no indication that Mr. Gary was assaulted by Mr. Deloach or the other male," authorities said.
In addition to being charged with Deloach's death, Gary is charged with domestic violence offenses, PPD added.
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