It was around 12:30 a.m. Monday when a 40-year-old woman was walking down Frankford Avenue toward the Frankford Avenue Bridge when a naked man emerged from the park and ran across the street.
He yelled an obscenity at the woman and jumped her from behind as she was crossing the bridge.
The man knocked the victim to the ground and tried to sexually assault her.
She managed to get up, jump the guard rail and ran down Frankford Avenue, screaming.
Those screams got the attention of a Philadelphia School District Police Officer, who happened to be passing by in a marked car.
Investigators say, when the attacker saw the marked car, he ran back into Pennypack Park and hasn't been seen since.
This is the latest in what appears to be a series of attacks on women in that area - Two women were assaulted as they walked in the park last October.
On October 1st, a 25-year-old woman was pushing a baby stroller on Algon Avenue when a man tried to wrestle her into the woods, but she managed to break free.
On October 23rd, a 28-year-old woman was grabbed from behind on Holme Avenue. In this incident the attacker also tried to drag her into the woods, but she punched him in the face and got away. The attacker in that case was wearing a mask.
Police say they have not officially connected the attacks, but acknowledge the crimes are very similar.
The victim in Monday morning's attack was back at the scene, talking to police. She gave them a description of the suspect that is almost identical to the description given by one of the earlier victims, except for the lack of clothing.
The suspect is described as a white man, about six feet tall, 30 to 40 years old, 5'11" tall and weighing more than 200 pounds. He had a light complexion and short blonde hair.
Detectives from the Special Victims Unit have been scouring the scene all day. They left with bags of possible evidence, but so far there is no sign of any discarded clothing or anything else that might lead them to the suspect.