Police sources told Eyewitness News that a 29-year-old mother and 43-year-old father were out with their 8-month-old baby and came home to the 20-year-old man stabbing his 8-year-old half brother with a butcher knife.
NYPD officials say the mother came out of the building, located at 147-25 94th Ave. around 5:20 p.m., bleeding, and pleading for help.
They say the woman, who was stabbed in the back, ran down to the corner and got help from MTA police, who called 911 for assistance.
Officers were on the scene within minutes, entered the building and responded to a fifth-floor apartment.
That's where they found the 20-year-old man, who cops say was holding his 43-year-old father in a headlock with a knife to his throat.
Officials say the officers ordered the suspect, repeatedly, to drop the knife -- but the suspect did not comply.
A 28-year-old officer then fired a single round, striking the suspect and saving the 43-year-old victim's life.
Two officers rushed the 8-year-old boy to the hospital because the ambulance was taking too long, according to police sources, but the child did not make it.
NYPD officials say two other victims were injured, the 29-year-old mother who was stabbed in the back, and the 43-year-old father who was also stabbed. An 8-month-old girl was also found in the apartment but was unharmed.
Police believe that the suspect and the 8-year-old victim were brothers or stepbrothers. They believe the incident stemmed from an apparent domestic dispute.
Officers rendered aid to the suspect, who was taken to the hospital where he later died.
The two officers were taken to North Shore University Hospital in Manhasset.
The NYPD is asking people to avoid the area surrounding 94th Avenue and Sutphin Boulevard due to the police investigation.
This story will be updated as more information becomes available.
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