NEW YORK (CBSNewYork) -- An NYPD officer is facing murder charges after an apparent love triangle turned deadly.
Police said 31-year-old Yvonne Wu, a five-year veteran of the force, was lying in wait at her ex-girlfriend's home in Brooklyn when she shot her ex and the ex's new lover, CBS2's Jessica Moore reported Thursday.
New video shows the chaos triggered when police say a scorned lover snapped.
"It was two shots and I have never ever in all the years I've lived here in my life seen anything like this," neighbor Pat Santi said.
Cellphone video shows Wu being frisked by fellow police officers Wednesday evening.
Wu was off-duty when she allegedly shot and wounded her ex-girlfriend, 23-year-old Jenny Li, and killed 24-year-old Jamie Liang, her ex's new girlfriend, according to detectives.
The deadly encounter has the community on edge.
"I can't believe it. It's awful," one woman said.
CBS2 has leared Wu and her ex broke up last month.
"I saw them all the time together," said Jeanette Vargas, a neighbor. "Just like anyone else, you can come home and find your lover or someone with someone else and you snap. So I don't think it had nothing to do that she was a police officer."
"How many breakups have you had in your lifetime? You gonna go and kill the person? You'd like to, but you don't actually take a 9mm and shoot them," Santi said.
Valerie Wades said she watched as paramedics tried desperately, but unsuccessfully, to save Liang.
"Ambulances with EMTs came and took the two victims out. One was, they were doing mad chest compressions," Wades said.
Police sources told CBS2's John Dias the deadly encounter may have been premeditated.
"We believe all three parties knew each other," said NYPD Assistant Chief Michael Kemper.
Sources said Wu waited inside her ex-girlfriend's home, which they shared at one time. When she returned with Liang, Wu allegedly fired off multiple rounds.
"It's a very good chance it is her service weapon," Kemper said. "One female, a 24-year-old, was found lying in the living room area and the second female, a 23-year-old, was found lying on the floor in the bedroom."
Police said Wu admitted to the shooting right away and that her weapons was inside the house.
"I would describe her as calm and collective and very forthcoming," said Kemper.
"Never in a million years did I think that it would've bee a cop who was the shooter. She just seemed so detached. Everybody else was like in hyper-drive and she was just so calm," Wades said.
Police said Wu's ex-girlfriend is in stable condition, but her injuries are serious.
Sources said Wu and her ex had remained in touch, but their post-relationship communication was "confrontational."
The state Attorney General's Office is handling the case since it is considered a police-involved shooting.
A GoFundMe has been set up to support Liang's family with funeral expenses. To find out more, click here.
CBS2's Jessica Moore and John Dias contributed to this report. Editor's note: This story was first published Oct. 14 and has since been updated.
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