The incident happened just before 11:30 p.m. Sunday, Dec. 31 at the River Pointe Apartment Complex on East Main Street (Route 25) in Riverhead.
Riverhead Police patrol units located a woman within one of the buildings with what appeared to be a stab wound to the chest.
The woman was uncooperative with officers at the scene and appeared to be under the influence, according to police.
Bystanders reported that a female suspect had fled the area on foot and was last seen running west on East Main Street.
A search of the area for the suspect was conducted by numerous units in the area along with the assistance of a K9 unit, however, she was not located.
The victim, a 44-year-old resident of the complex, was transported from the scene to Peconic Bay Medical Center in Riverhead by Riverhead Ambulance for treatment of her wound, which was non-life threatening.
The Riverhead Detective Division was contacted and responded to the scene.
There is an active investigation and anyone with information is asked to contact Riverhead Police at 631-727-4500.
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