Inmates set several buildings on fire during a riot Friday night at Northpoint Training Center, a state prison in Boyle County, authorities said.
Mercer County Sheriff Chris Kehrt said he and other law enforcement officials were told during a late-night briefing that 80 to 100 inmates might have been involved in the riot.
The governor's office said Saturday morning that a news conference will be held at the prison at 4 p.m. Northpoint, a medium-security prison about 5 miles north of Danville, houses 1,200 inmates.
One inmate complained of chest pains, and two others had head injuries, Kehrt said.
The buildings set afire included an infirmary, a chow hall and two dormitories, Kehrt said. The Danville Fire Department fought the fires with a ladder truck extended over the two fences surrounding the prison, Kehrt said.
A Kentucky State Police special response team fired tear gas to quell the riot, Boyle County Deputy Sheriff Jim Wilcher said.
Kehrt said a breeze blew some of the tear gas into the ranks of firefighters and police.
No hostages had been taken during the incident, Wilcher said, and Kehrt said no inmates escaped from the prison property.
Kehrt said all the prisoners had been "compliant" since about 9:30 p.m. He said a group of more than 80 "agitators" could be seen marching to a clearing beneath a light, where they sat on the ground.
Kehrt said he saw corrections officers securing the inmates' wrists with zip ties.
Kehrt said guards were stationed around the prison and that police dogs and their handlers were patrolling outside the fence.
The only law enforcement officials who went into the prison were members of an emergency squad. Other police agencies were called in for stand-by, Kehrt said.
He said several police agencies and fire departments from neighboring communities were on the scene.
Mendolyn Cochran, public information officer for Northpoint, told the Danville Advocate-Messenger that the prison had been on lockdown since Tuesday, when 10 to 15 Hispanic inmates assaulted a black inmate and a white inmate.
Around 6:30 p.m. Friday, inmates set fires in trash cans in the wings of one building, Cochran told the newspaper.
Once the fires have been knocked down, corrections officials will assess the damage and then determine how many inmates will have to be moved to other facilities across the state, Kehrt said.