In a tragic incident on Thursday, a Port Authority police officer fatally shot his sister and left their mother critically injured before taking his own life.

New York police officers were dispatched to the Bronx apartment early Thursday morning following a 911 call from a receptionist who reported the sound of gunfire around 8 a.m. Upon arrival, authorities discovered the lifeless bodies of a 55-year-old man and his 59-year-old sister, both with gunshot wounds to the head. Meanwhile, their 86-year-old mother, who sustained a gunshot wound to the face, was immediately transported to a hospital, according to WCBS.

Investigators recovered two firearms at the scene.

Sources within law enforcement revealed that the shooter had a 20-year tenure with the Port Authority, most recently serving at LaGuardia Airport.

The identities of the individuals involved have not been disclosed by the police.

According to WABC, the officer’s body was discovered in a hallway, alongside a firearm and his Port Authority Police badge. His sister was found in a bedroom, while their mother was located in another room and remains in critical but stable condition.

Neighbor Jane Burbank told WCBS the 59-year-old woman had lived in the the apartment for years and that her mother and recently moved in with her.

“She had nieces and nephews. She had a big family,” Burbank said. “She was a wonderful person, she was full of life. She loved to dance, she loved to get people together, she loved to cook, she loved to eat. She loved to travel, and was looking forward to her retirement so she could travel more.”