GREENVILLE, Ill. (AP) _ Guards regained control of a medium-security prison today one day after inmates rioted to protest a nationwide lockdown of federal prisons.

A SWAT team rescued a group of employees who had barricaded themselves in part of the facility to protect themselves from the prisoners. In all, 10 staff members were hurt, most with cuts and bruises.

The uprising was one of a number of violent incidents in several states in which prisoners set fires, threw baseball bats and broke windows.

The sporadic violence, some of it apparently triggered by Congress' refusal to reduce penalties for crack convictions, began late Thursday at the federal prison in Talladega, Ala. It spread Friday to those in Memphis, Tenn., Allenwood, Pa., and to the town of Greenville 40 miles east of St. Louis.

Tyrane Martin, a spokesman for the federal prison here, said authorities regained control of the facility early this morning. The disturbances at the other prisons were brought under control on Friday.

It was not immediately clear whether any of Greenville's approximately 1,200 inmates were hurt or how many were involved in the violence.

Police Sgt. Lou Lorton, who entered the prison shortly after the disturbance began, said prisoners emerged in small groups from their dormitory stronghold and surrendered.

The mayhem began when some inmates refused to return to their cells as part of the national lockdown, and took over a housing unit.

Four staff members were treated at Utlaut Memorial Hospital, and all but one _ who was in good condition _ have been released, said spokesman Alan Gaffner.

The prison was brightly lit from its buildings out to the barbed-wire perimeter early today. No escape attempts were reported, but emergency personnel guarded the roads around the prison with lights flashing from fire trucks and other vehicles. The prison is bounded by farmland on two sides, by Interstate 70 on the south and by the city limit on the north.

In Memphis, crews were still dousing what's left of a series of fires set during a disturbance that at one point had more than 800 inmates roaming unsecured through a recreation yard. At least 50 people were treated for smoke inhalation and other injuries.

In Pennsylvania, about 150 inmates went on an hourlong rampage Friday in a dining hall of a medium-security prison, pulling fire alarms and breaking windows, the prison said in a statement. A staff member was burned when a hot liquid was thrown in her face. Her condition was not available.

Local television and radio stations reported the disturbances may have been linked to the congressional vote not to reduce the penalty for crack cocaine convictions.

Two people who were trapped inside during the trouble Thursday night at the federal prison in Talladega, Ala., also said that was the reason for that disturbance. Thirteen people were injured and inmates caused $1 million in damage by setting fires and smashing windows with baseball bats.

A law enforcement officer elsewhere in the prison at the time also said inmates were upset about the vote. The officer, who spoke on condition of anonymity, said some inmates had been agitated since the Million Man March in Washington on Monday.

The Rev. Jesse Jackson criticized crack sentencing laws at the rally, saying they disproportionately affect blacks.

U.S. Bureau of Prisons spokesman Bill Bechtold wouldn't comment on whether the vote played a role. Corliss Moragne, spokeswoman for the prison in Talladega, said the investigation was incomplete.