A man was killed and another man was injured when gunfire erupted at a gathering in northwest Atlanta early Sunday morning.

The shooting happened at a reunion event for the former Bowen Homes public housing community, according to a Facebook discussion group created for the community. Officials said an Atlanta police officer returned fire when he heard gunshots ring out in the crowd, prompting the GBI to investigate the incident as an officer-involved shooting.

Gabriel Parker, 38, was killed during the shooting, according to a GBI statement.

Nearly 1,000 people were at the gathering in the 800 block of James Jackson Parkway about 1 a.m., Atlanta police said in a statement. Bowen Homes was Atlanta’s last standing public housing project when it was demolished in 2009.

After arriving in the area, an officer spotted two people shooting at each other, the statement said. The officer pulled out his weapon and returned fire, officials said.

Police found two handguns at the scene of the shooting. No officers were injured during the incident, according to the GBI.

“At this time it is unclear who shot whom, but two people sustained gunshot wounds,” Atlanta police said.

Parker was pronounced dead at the scene, and a second man was rushed to a hospital.

Parker’s family has said he was attempting to break up a fight happening at the event when he was shot. Investigators have not confirmed that claim. A vigil was held Sunday evening to commemorate Parker’s life.

Parker’s body was taken to the Fulton County Medical Examiner’s Office for an autopsy.