ATLANTA (AP) — A second person has died after a fraternity picnic at an Atlanta park ended in gunfire on Saturday.

Atlanta police said Monday that Justin Minnitee, 23, died from his injuries.

Witnesses have said that Minnittee arrived at the picnic that Kappa Alpha Psi was holding at Coan Park, southeast of downtown Atlanta, and began arguing with people attending the event put on by the historically Black fraternity.

“From what we know at this point, there was an uninvited guest that arrived to the location, which led to a confrontation, which led to guns being produced and shots being fired between the two individuals,” Atlanta Police Lt. Andrew Smith told WAGA-TV.

Investigators say at least two people exchanged gunfire. Authorities on Saturday said Andrew Pearson, 33, died at the park after being shot in the head. WSB-TV reported that Pearson was a member of Kappa Alpha Psi.

Minnittee died later after being hospitalized.

Two other people took themselves to the hospital. One was grazed by gunfire, while the other was admitted to be treated for injuries.

Police said they’re still investigating.