NEW YORK -- A police officer shot and killed a man who allegedly stabbed an 8-year-old boy to death in Queens on Thursday, the New York City Police Department said.

The stabbing likely stemmed from a domestic dispute, police said, but the details were still unclear. Police said the 20-year-old suspect and the 8-year-old male victim may be brothers or step-brothers. No names were immediately released.

The incident occurred inside an apartment building on 94th Avenue in the borough's Jamaica neighborhood. Around 5:20 p.m., police say a 29-year-old woman who had been stabbed in the back left the building and ran down the street to MTA Police to ask for help. At the same time, the building's security desk called 911.

Officers responded within three minutes and went to a fifth-floor apartment after speaking to a witness, police said.

Police say when officers entered the apartment, they found the suspect holding his 43-year-old father at knifepoint.

The suspect allegedly refused repeated commands to drop the knife, and an officer then fired one round, striking the suspect, police said. Officers immediately rendered aid, and the suspect was taken to an area hospital, where he died.

According to police, an 8-month-old baby was also in the apartment at the time of the incident, but the baby was unharmed.

"Just a reminder of being a New York City police officer, what they have to walk into and decisions they have to make quickly. And by making those decisions, they saved two lives tonight," NYPD Chief of Patrol John Chell said.

Footage of the shooting was captured on police body cameras.

Police say the 29-year-old woman and the 43-year-old man were both taken to area hospitals to be treated for their injuries. Both are expected to survive.

The investigation is ongoing.

Stay with CBS2 News and CBSNewYork.com for the latest on this developing story.

In:
• Queens
• NYPD