A fire set by a Pennsylvania inmate at the State Correctional Institution at Dallas on Sunday led to a state of emergency at the prison and sent at least seven corrections officers to hospitals.

The fire inside Cell Block KB, the Restricted Housing Unit, broke out about 1:10 p.m., forcing Superintendent James T. Wynder to lock down the entire facility. The Restricted Housing Unit is a segregated area for difficult or high-profile inmates, including accused killer Hugo Selenski. Forty-six of the prison's nearly 2,000 inmates are housed there.

State police Cpl. Nicholas Gushka said an inmate set fire to his cell, sparking the blaze. Corrections officers had the fire under control within 10 minutes, according to Assistant Superintendent Robin Lucas.

All the Restricted Housing inmates were moved to other areas of the prison, Ms. Lucas said. No inmates were injured during the fire or the evacuation. As of 6 p.m., two officers were being treated in the emergency room at Wilkes-Barre General Hospital, said spokesman Kevin McDonald.

Three officers were treated for smoke inhalation at Geisinger South Wilkes-Barre and released, hospital spokeswoman Betsy DalSanto said. Two more officers were treated for smoke inhalation at Geisinger Wyoming Valley Medical Center, Plains Township, and released, hospital spokeswoman Amy Lingobardo said.

State police said an eighth officer may have been involved, though hospitals accounted for a total of only seven.