A 9-year-old girl returning home on her birthday Monday night opened her door to a horrifying scene: Her mother and two sisters had been shot and killed, the police said.
On a walkway outside the apartment in a housing project in Brooklyn’s Brownsville neighborhood, her father also lay dead, the police said. The authorities believed that after killing the girl’s other family members, he shot himself.
Officials had not publicly identified any members of the family as of Tuesday morning and were working to determine a motive for the brutal killings. In a television interview, the city’s police commissioner, Dermot F. Shea, said that the shootings appeared to be “domestic in nature” but that investigators were looking for more information.
“It’s just a terrible situation all the way around,” Mr. Shea said in an appearance on NY1.
Investigators found one gun with the man and another in the apartment, the police said. The mother, 45, and two sisters — one 20 and the other a teenager — were all found shot in the head at around 11:20 p.m. The 9-year-old girl, who called 911, was not believed to be injured.
The father, 46, was found with a wound to the head that officials believed was self-inflicted. Mr. Shea said that the police had video of the incident that showed the gunman leaving the apartment before killing himself.
The family appeared to have only recently moved into the apartment and had no history of domestic violence calls, the police said. The gunman had no prior arrests, the police said.