By Alicia Roberts

PHILADELPHIA (CBS) — Philadelphia police say a woman was beaten with a pipe and killed inside of an Old City office building Wednesday afternoon. The assault happened inside the Regus shared office space near 3rd and Chestnut Streets around 2:15 p.m.

At this hour, police are still interviewing the alleged attacker at police headquarters but say they do expect charges to be filed.

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Police say a 31-year-old woman sitting at a receptionist desk on the eighth floor of the Regus building was attacked from behind by a man armed with two metal pipes.

“The male walked up to her and began hitting her in the head and he hit her repeatedly in the head. We believe she was struck at least five times,” Philadelphia Police Chief Inspector Scott Small said.

Police say the brutal attack was committed in front of at least 10 witnesses, many of who called 911.

Police arrived in minutes to find the 31-year-old victim unresponsive.

“She had defensive wounds on both of her hands,” Small said.

Moments before, as officers were entering the lobby of the building, the alleged attacker walked off the elevator.

“He was carrying a bag, turns out that bag had two metal pipes in the bag. Both of those pipes in the bag had blood on them and he was covered with some blood,” Small said.

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Police say the accused attacker rents an office on the same floor and recently learned he was going to be evicted.

“They told me what office he was in. I like picture the guy, I know who he is. There is not a lot of people on the floor,” said Sean Riskowitz, who works on the eighth floor.

Riskowitz was in his office when the attack happened. He walked by the crime scene as he left work Wednesday evening.

“Blood on her desk and other chairs and items strewn about,” he said.

He’s shocked by what happened and heartbroken for the victim.

“She would run the office. I would come in every day and see her, very nice girl,” Riskowitz said.

Police have not released the name of the accused attacker.

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Meantime, CBS3 spoke with the victim’s father. He says they are grieving this loss and still have so many questions. They’re asking for privacy as they process their loss.

Alicia Roberts