Ashley Guimont, 44, opened fire on Alex Carter, 47, inside their home on Townehouse Drive after a physical confrontation erupted around 2:30 a.m., according to police.
Guimont called 911 moments after the shooting. Carter was rushed to John T. Mather Memorial Hospital in Port Jefferson, where he was pronounced dead, the police explained.
Guimont was arrested at the scene and charged with Murder 2nd Degree by Homicide Squad detectives.
She was held overnight at the Fourth Precinct and is set to appear in First District Court in Central Islip for arraignment on Saturday, July 5.
Anyone with information about the case is urged to contact the Homicide Squad at 631-852-6392.
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