The blast occurred at the Escambia County Jail's Central Booking Facility in Pensacola at around 11 p.m. local time (midnight Thursday ET), officials said.
Kathleen Castro, the county’s public information officer, confirmed the deaths to NBC News and said that both prisoners and corrections officials were among the wounded.
About 600 prisoners were in the building at the time. Uninjured inmates were being moved to other detention facilities, authorities added.