At least 28 people have been injured in clashes between guards and rioting inmates at a prison in the Sri Lankan capital, Colombo, police say.
Reports say guards opened fire to restore order and most of the injured are prisoners with bullet wounds.
Police say inmates were angered by moves to curtail drug smuggling in the Welikada (or Magazine) jail.
A local resident told the Associated Press that disturbances had been going on for several days.
Police spokesman Ajith Rohana said 24 prisoners and four guards had been hurt in Tuesday’s violence.
AP quoted a doctor at Colombo National Hospital saying most of the prisoners had gunshot wounds. Three guards had been hit by stones and another had a fractured leg.
None of the injuries was life threatening, Dr Prasad Ariyawansa said.
Pictures from the scene showed soldiers deployed outside the jail as black smoke billowed into the air from inside the complex.
Prisoners are reported to have set fire to a kitchen and an administrative building.
A number of inmates have been demonstrating on rooftops with a banner calling for the prison chief to be removed.
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