Police say someone called 911 from the apartment on 30 Drive near 23rd Street in Astoria after 9 p.m. Monday.
Heavily armed police responded to the home after the bodies of two women, a man and a boy believed to be just 5 years old, were found on the first floor.
Investigators now believe this is the result of a triple murder-suicide.
We do not know if the victims are related at this point.
Police have yet to say who they believe the shooter is as they work to figure out what led to the savagery inside.
"It was a very robust turnout and response from the detectives' side as well as the patrol side, still on the scene. We have a real-time crime van just over my shoulder, still poring over data, not just from that building, from that apartment, from this entire area," NYPD Chief of Detectives Dermot Shea said.
Investigators are speaking to the person who placed the initial 911 call. They are also looking into prior 911 calls made from this address.
A weapon was recovered by police at the scene.
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