Police in York said 18-year-old Denzel Turane was gunned down during the party Sunday morning at a home in the city.
Officials said a 14-year-old girl was critically injured and a 16-year-old girl was grazed by a bullet.
Authorities said a youth who was 16 at the time but turned 17 on Monday has been charged with criminal homicide, attempted homicide and aggravated assault.
Police said they wanted to talk to three other people and located two of them Monday but are still seeking the third.
