Sri Lanka commandos sent to stop riot

COLOMBO, Sri Lanka (CNN) -- Government authorities said Sunday they have surrounded a prison in southern Sri Lanka where inmates earlier in the day went on a rampage and took 11 staff members and guards hostage.

Army Brig. Sanath Karunaratne, a military spokesman, said an "anti-hijacking commando team" had been dispatched to Tangalle prison in the port town of Tangalle, about 200 kilometers (124 miles) south of the capital city of Colombo.

Karunaratne said 12 women prisoners who had escaped surrendered to police late in the day.

The riot began at 3:30 p.m. (5:30 a.m. EDT) when about half of the prison's 400 inmates took the hostages and seized control of the prison's armory, a senior police officer in Tangalle told CNN.

The prisoners were holed up in the prison compound, he said.

Most of the inmates are serving time for deserting the army, though the cause of the riot was unclear, the officer said.

Army and navy personnel have surrounded the prison and have planned an action to rescue the hostages, Sri Lankan authorities said.

Authorities have imposed a 6 p.m. to 6 a.m. curfew in Tangalle.