A second teenager died this afternoon after a shooting Friday night at a girl's 18th birthday party outside of Philadelphia that left eight other people wounded.
One victim, who has been identified as a 19-year-old man, died early today and a second died this afternoon, according to a spokesman for Crozer-Chester Medical Center, where nine of the victims were taken.
Of the other people wounded in the attack, four remained hospitalized in stable condition, while the others at Crozer-Chester were released by this afternoon, the spokesman said.
A 10th person was treated at another hospital, he said.
All of the victims were teenagers, a source told ABC News affiliate WPVI-TV in Philadelphia.
"Someone just opened the door and started firing," an unnamed source told Chester County's Daily Local.
One victim was shot in the head, and two firearms were recovered at the scene, according to Chester police.
Police said today they have one suspect, a 17-year-old male, in custody, but they have not said what they believe led to the shooting at 11:30 p.m. Friday at Minaret Temple No. 174 in Chester, Pa., which is 15 miles outside Philadelphia.
Police brought dozens of people in for questioning who were at the hall at the time of the shooting. The building was reportedly locked down.
Preliminary reports indicated that the shooting victims ranged in age from 15 to 20 years old, Chester Police Department Chief Darren Alston told the Daily Local.
Chester Mayor Wendell Butler Jr. told the Philadelphia Daily News that he visited the scene of the incident early this morning.
"It probably was a young persons' party, probably people in their late teens," Butler said.
The mayor told The Associated Press that there were teens as young as 13 at the event, some of whom had come from Philadelphia.
"I asked one of them, 'How did you know about this?' He said, 'It was on Facebook,"' Butler said. "I said, 'Does your mother know where you are?' It's like 11 o'clock at night. He tells me she doesn't care. And I said, 'Oh, my goodness. I guess that's part of the problem."'
Butler said witnesses who were not injured in the shooting were taken by bus from the temple to the Chester police station.
"That's where our detective division is. We have to interview everybody," Butler told the Philadelphia Daily News. He said he understood that private security was at the event.
The incident follows a rash of shootings in the Chester area last summer that left four people dead over an eight-day period, which led Butler to declare a state of emergency and a 9 p.m. curfew. The city had two dozen homicides in 2010.
According to police, the local drug trade was the cause of the majority of the violence.
Anyone with information should contact Detective Randy Bothwell at (610) 447-8430.