A dispute between neighbors turned deadly Friday afternoon as a man fatally shot a man and woman in a Manhattan building — where a fire was started — before killing himself, the city police department said.

"He snapped, but for what? Now they're all dead," said Mary Hall, a resident of the building.

Police responded to a 911 call shortly after 2:50 p.m. to an apartment building on West 131st Street between Malcolm X Boulevard and 5th Avenue in Harlem.

Police officers said they found a 78-year-old man lying in the first-floor hallway with a gunshot wound to the head.

They then heard a man yelling, "Come and get it!" from inside a first-floor apartment. He had barricaded himself inside. While police secured the scene, they said they noticed smoke emanating from inside his apartment.

Once police got inside the apartment, according to investigators, they found a 59-year-old man, who was not identified as of this writing, with a self-inflicted gunshot wound to the head.

Firefighters then got the two-alarm fire under control. It's not confirmed if the suspect started the fire.

Emergency service unit officers found a 62-year-old woman shot in the head on the second floor of the building. Neighbors said she was married to the 78-year-old victim.

Law enforcement sources originally told NY1 that the shooting stemmed from a romantic dispute, but police later would only say the men had a dispute before the suspect shot the 78-year-old in the head and then shot the woman. Police said they recovered two firearms from inside the suspected shooter's apartment.

Neighbors said there had been issues with the 59-year-old man, including a number of noise complaints.

The identities of the victims were not confirmed at this time.

The investigation is ongoing.