Basil Gray, 54, lived alone on the fifth floor and was found lying on the floor unconscious with gunshot wounds in the Bushwick Houses.
Family members had not heard from the man since Thursday, so they called police. The man was pronounced dead on the scene by EMS.
CeFaan Kim has the latest from police:
The man's neighbor, Ana Devalle, 62, was found Friday with her hands bound and was shot in the head multiple times.
Officers say there is a 'strong possibility' that the man did not die today and died on Friday as well.
"It is a strong possibility that he died on the same date and approximate time as his female neighbor," says NYPD Deputy Chief Michael Kemper.
The motive surrounding the man's death is unknown, and the connection between the two incidents is currently unknown.
Police say there are no signs of forced entry at either apartment. Detectives believe it might be possible that the victim who was found Sunday heard the gunshots next door on Friday and met his killer when he came out to check on his neighbor - or the other way around.
A weapon was not recovered in the man's apartment. Police also did not find any signs of robbery in his unit, but investigators caution that detectives are just beginning to investigate inside his home.
As for Devalle's apartment, there was a small amount of money missing from Friday's incident.
Police say they are conducting door-to-door searches within the Bushwick Houses to ensure the safety of residents and are in the process of questioning every single person in the building.
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