On the evening of Wednesday, July 22, 2026, deputies responded to a reported shooting at Northwest First Street and Railroad Avenue in Reserve, Louisiana. At about 9:38 p.m. they found 18-year-old Jacoi Cosey in the back seat of a vehicle with multiple gunshot wounds; he was pronounced dead at the scene. Initial investigators reported the shooting appeared connected to the robbery of Cosey’s firearm.

The St. John the Baptist Parish Sheriff’s Office identified three suspects within a day and arrested them on July 23, 2026. The suspects were named as 20-year-old Brandon Blackmore of LaPlace, 22-year-old Tyshley Marks of Reserve, and 17-year-old Emanuel Rayfield Jr. of Reserve. Each was booked on one count of second-degree murder and one count of armed robbery with a firearm and held on $475,000 bond.

The St. John the Baptist Parish school system, where Cosey was a student, offered counseling and mental health services to students and staff after his death. Does anyone have information about Jacoi’s last known movements or witnessed activity near Northwest First Street and Railroad Avenue that night?