Syrian authorities say they have restored order at a prison near the capital, Damascus, after a riot there broke out Saturday.

The official SANA news agency says security forces took action at Sidnaya prison Sunday and put down the violent protest started by prisoners convicted of extremism and terror crimes.  The agency did not say whether there were any casualties.

But the London-based group - The Syrian Observatory for Human Rights - said rioting by Islamist inmates, some of whom have been held at Sidnaya without trial, continued Sunday.  

The group said 25 prisoners were killed and many more wounded when security forces opened fire to end the disturbance, and that some prisoners fled to the roof, fearing for their lives.

Some information for this report was provided by AFP and Reuters.