The victim, Nakia Bruton, 42, had been stabbed once in the chest on Winnikee Avenue and later died at Vassar Hospital, said City of Poughkeepsie Det. Lt. Matt Clark.
Bruton was driven to the hospital in a private vehicle, and the hospital notified police of his death, Clark said.
Following his death, the girlfriend, Marcena R. Edwards, 43, told police that Bruton had gotten into a verbal argument with a group of teens who walked in front of the vehicle and that one of the teens had stabbed him, Clark said.
Police put out a call to the public for help in finding the teens, or any surveillance video.
But officers later uncovered that Edwards had stabbed the father of her child while arguing in the vehicle, he added.
The infant was in the car at the time of the murder, Clark said.
Edwards was charged with first-degree manslaughter and is being held pending her arraignment.
Police are still asking anyone who was in the area of Winnikee Avenue on Thursday, Sept. 14 between 5:40 and 5:50 p.m., to call the City of Poughkeepsie Police at 451-7577.
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