Eight California prison guards and seven inmates were taken to hospitals Wednesday after a fight between two inmates quickly raged out of control and required live ammunition to stop, corrections officials said.

Officers fired 19 bullets from semiautomatic rifles and three hard-foam rounds to break up the melee at Pelican Bay State Prison near the Oregon border, reports the Associated Press.

Six of the eight injured guards were treated and released. Two were hospitalized with what officials called significant injuries but were expected to be released soon. One of those officers will eventually need surgery for an injured shoulder, said Terry Thornton, a spokeswoman for the California Department of Corrections and Rehabilitation.

“They all had ... facial injuries, bumps, bruises, contusions,” she said. “It's a frightening incident. It's frightening to have inmates just swarm you to overwhelm you and attack you.”

Five of the seven injured inmates suffered gunshot wounds. Their conditions were not known.