Police responded to an apartment building on Johnson Avenue in the Riverdale section just before 8 a.m.
Investigators say the doorman of the 20-story building, the Winston Churchill, heard a gunshot and called 911.
When police arrived, they say they found a 55-year-old man lying in a first-floor hallway with a gunshot wound to the head. Next to his body was a firearm and Port Authority Police ID.
Emergency crews found a 59-year-old woman dead with a gunshot wound to her head in a bedroom, and their 86-year-old mother, who had been shot in the face, in another room. She was rushed to Harlem Hospital, where she is said to be in critical but stable condition.
Detectives believe the man fatally shot his sister, shot his mother and then shot himself. Police believe he was a Port Authority Police officer.
"It's a terrible shock, and I don't understand what happened with the brother. I don't get it at all," said the victim's friend Jane Burbank.
She says she knew the 59-year-old woman's parents.
"They just had a big anniversary party... 65 years together or more," Burbank said.
Friends say the 86-year-old mother had recently moved in with her daughter.
"She was a wonderful person," Burbank said. "She was full of life. She loved to dance. She loved to get people together. She loved to cook. She loved to eat and loved to travel and was looking forward to her retirement."
Detectives are investigating the incident as a domestic shooting, and an apparent murder-suicide.
As to what led to the tragic family disturbance, it's still not clear.
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