Friday night police released a sketch and description of the suspect.
He's described as a black man, 33-38 years old, 190-200 pounds. He's said to be about six feet tall with a dark complexion and medium build. He's said to have short, black hair and was wearing a dark hooded jacket, dark sweat pants, dark footwear and a red and royal blue striped hat with no logo.
The young woman and her boyfriend had just arrived home at the Clinton Court Apartments.
As they tried to enter their fifth floor unit, the suspect was waiting and acting like he was talking on his cell phone.
"He immediately turns around upon their presence, turns around with that knife, approaches them immediately and forces them right into the apartment," Captain John Darby of the Philadelphia Police said.
The suspect remained in the apartment for nearly an hour and a half and brutally raped the woman at knifepoint.
"Keep in mind the victims were bound and gagged and in some cases blindfolded inside that One woman, who didn't want to identified, heard the victims' cries for help.
"All of sudden I hear a woman screaming and she was screaming help, please help us, call 911," the woman said.
This home invasion is the fourth in a series of knife-point attacks in a week in an 8 or 9 block square area, all east of Broad.
In the 1100 block of Lombard, a knife-wielding man followed a 22-year-old woman in the foyer of her apartment building, but fled when she screamed, alerting neighbors.
"It's pretty scary. And it generally feels like a safe neighborhood," said Beth Fogarty of Center City. "I'm never usually concerned about it, but when you hear about these incidents it's definitely worrying."
The Clinton Court Apartments has a sign claiming it has 24 hour video surveillance, but residents say the system wasn't working.
On Friday, a sign could be seen stating the locks to the building had been changed.
Two other young women have been robbed at knifepoint in the area. Both were walking alone at night.
In all cases, the suspect brandished a knife and has the same general description.
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