South Carolina Department of Corrections said all staff from the McCormick County Correctional Institution are safe and accounted for.
McCormick is classified a Level 3 facility, housing violent offenders with longer sentences and inmates with behavioral problems, according to the South Carolina Department of Corrections.
The sheriff's office said there was also a fire at the SC prison, located 78 miles west of Columbia, SC.
Rumor Correction: Incident is isolated to one housing unit and all inmates are contained.
According to Jason Brown with McCormick Emergency Services, a couple of prisoners from one housing unit were on the roof trying to escape.
All inmates are contained following an incident at a SC maximum-security prison Wednesday evening, the Department of Corrections said.
There is also a fire in the facility, WIS reported.
The prison is approximately 75 miles west of Columbia, the state capital, and houses about 900 men.
Check back for updates on this developing story.