Victim's Neighbor: "He told her if she was sending him to jail for beating her up, he'd kill her first."By Meghan Schiller

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PITTSBURGH (KDKA) — Allegheny County Police are searching for a man accused of fatally stabbing his girlfriend during an argument in Pitcairn.

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Derrick Avant, 59, is wanted in for allegedly stabbing, Alison Fritzius, 55, at her Pitcairn apartment on Hillside Avenue. She died from her injuries.

(Source: Allegheny County Police)

Police tell KDKA that she was stabbed just before 7 p.m. Sunday and ran next door to her neighbor’s house to ask for help. The neighbor told KDKA she started banging on the door and asked him to call 911. When he asked her who did that to her, she answered, “My boyfriend D,” according to the neighbor.

Police said Avant ran from the scene and he is believed to be traveling on foot somewhere in the Pitcairn area. They do not believe he has the means to travel far.

Avant is described as 5-foot-9-inches, very skinny, balding with gray hair on the sides and missing most of his front teeth.

Investigators believe he stabbed Fritzius following an argument inside her apartment.

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KDKA’s Meghan Schiller talked with one man who was staying in another apartment inside the building. He said he heard all of the fighting and yelling, but his roommate told him that it “happened all the time” and “don’t get involved.”

“He told her if she was sending him to jail for beating her up, he’d kill her first. And he did,” said Kevin Kotewicz. “She was screaming and they were screaming at each other.”

Insp. Andrew Schurman said this was not the first time that Avant tried to harm her, saying the couple “had an on again off again relationship and it was described by the Pitcairn Police Department as ‘tumultuous at best.’”

He added that there was a series or a history of domestic incidents with them and “she had a PFA against Mr. Avant, so we’re not sure what triggered him to go to the residence,” said Insp. Schurman, Allegheny County Police Department.

Avant has a lengthy prior criminal history. He’s faced charges for aggravated assault, harassment and drugs.

He’s now wanted for criminal homicide.

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Anyone with information in his whereabouts is asked to call the Allegheny County Police Tipline at 1-833-ALL-TIPS (1-833-255-8477). Anyone who spots him is urged to call 911 immediately.

Meghan Schiller