This post has been updated.

Police described a bloody scene in a North Philadelphia alley where a 19-year-old woman plunged 39 feet to her death after falling from a rooftop early Wednesday evening.

The teen, according to investigators, was at a party in a house just west of Temple University's main campus on 18th Street near Arlington when she somehow tripped over a 10-inch ledge and fell to the concrete below. Police in North Philadelphia's 22nd District received numerous calls just after 5 p.m., and found her lying on the ground in a narrow alleyway between buildings. Cops said dozens of teens were still on the roof when they arrived at the scene, and beer cans and bottles were strewn about the house.

The university's "Spring Fling" is being celebrated this week. Police also said they could see students and their friends partying on the roofs of several other houses in the area, and ordered them to move off the roofs.

Police said the fall appeared to be accidental, but detectives were investigating to rule out any foul play, said Chief Inspector Scott Small at the scene as students milled around the blocks and hung out on stoops in the mild weather early Wednesday night. Eight witnesses were taken to the Central Detective Division to be interviewed.

Police and Temple officials said the woman is not a Temple University student. Reportedly, she attended another area university.

She was rushed to Temple University Hospital, where she was pronounced dead at 5:51 p.m. Police described a gruesome fall down the narrow alley, in which the victim likely "ricocheted" off building walls on her way down.

Small said a movable ladder from the second floor up to a hatch in the third-floor roof was how the party-goers gained access. The roof had no railing.

The young victim was not identified Wednesday, pending notification of her family.

"It's tragic. You can't let some people up on the roof if they look intoxicated," said Temple student Nick Cross, 22, a senior business major as he watched police investigate from across the street.

His friend, Ari Remetz, 22, a senior religion major at the university, said he'd been on a roof celebrating "Spring Fling" earlier in the day.

"I'm not ever going on the roof again," Remetz said.