The NYPD says five people were found shot to death in four separate shootings overnight. Police sources say one of the incidents is being investigated as a murder-suicide.

According to authorities, the first shooting happened around 11 p.m. on Schenectady Avenue in Crown Heights. They say a 37-year-old man was shot in the neck and killed. As of Thursday morning, a person of interest was being questioned.

Approximately a half-hour later, police responded to another shooting near Atlantic and Rockaway avenues in Ocean Hill. Police say a 28-year-old man was fatally shot in the torso. Detectives say they believe the shooter fled in a blue Mercedes.

Around 1 a.m., police responded to 386 Second St. in Park Slope. Upon arrival, officers discovered a man and a woman, both 34 years old, with gunshot wounds to the head. They say a firearm was found near the man. A friend of the male victim tells News 12 the man lived in the building and grew up in the neighborhood.

Following the apparent murder-suicide, another shooting unfolded in Clinton Hill. Police say a 35-year-old man was shot in the head on Hall Street around 2:45 a.m. He was rushed to the hospital, where he later died.

Police say all four incidents appear to be unrelated.