NEW YORK (CBSNewYork) — The girlfriend of a man who was killed in a stairwell shooting broke down in tears on the stand Tuesday, as testimony in the manslaughter trial of NYPD officer Peter Liang continued.

Officer Peter Liang is accused of firing his gun in a darkened stairwell at the Pink Houses in East New York back in 2014, killing Akai Gurley.

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Melissa Butler said Gurley was visiting her apartment at the Pink Houses that day and they decided to take the stairs when he left because the elevator wasn’t working, WCBS 880’s Irene Cornell reported.

Butler said she heard a door open above them, heard a shot and ran, with Gurley collapsing on the fifth floor landing. The sobs came as she relieved the terrible moments — running for help, getting a neighbor to call the police, seeing the bullet wound in Gurley’s chest and trying to revive him. 

When asked if she ever saw Liang, Butler said no, claiming he never came to help or see what happened.

Police officer Shawn Landau testified that he and Liang were both in shock after Liang’s gun went off by accident, Cornell reported.

“I’m fired,” said Liang, according to Landau’s testimony.

Landau said he and Liang went back and forth about who was going to call in the incident. Landau said neither him or Liang knew the bullet hit anyone.

“We were just standing there,” Landau said.

Landau said by the time they made their way down the stairs to see what happened, they found Gurley with his girlfriend, Melissa Butler, leaning over him, weeping. Landau said that Liang yelled out “oh my God, someone’s shot.” Moments later, he collapsed on the floor, crying himself. 

NYPD Lt. Vitaliy Zelikov said on the stand Jan. 28 that Liang told him that he shot Gurley by accident.

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Zelikov told the courtroom Liang “appeared frozen” and was “staring off into space” after the shooting, WCBS 880’s Irene Cornell reported. The lieutenant described Liang as shaken, distressed and hyperventilating after shooting Gurley.

A 911 call from a building resident seems to allege that police did not help, CBS2’s Lou Young reported. The caller relayed CPR instructions to Gurley’s girlfriend, Melissa Butler, who was also on scene at the time of the shooting:

9-1-1 Operator: Tell her to pinch his nose, put her mouth on top of his and breathe into his mouth.

9-1-1 Operator: Let me ask you something, are the cops assisting her?

Caller: They’re right here. They’re not with her. They’re trying to call back-up? I don’t know.

9-1-1 Operator: Does she have anybody else with her?

Caller: No, she’s alone with him. She’s still doing CPR with him right now.

9-1-1 Operator: I’m sending a message to hurry up.

Caller: Yeah, he’s not breathing.

Gurley’s family has brought a wrongful-death lawsuit on behalf of his estate and his young daughter. At an announcement of the suit in May, the girl’s mother, Kimberly Ballinger, vowed to “be in court every time to make sure that justice for him is kept, that justice for him is received.”

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Liang faces up to 15 years in prison if convicted.