A shadowy Islamic fundamentalist movement claimed responsibility Saturday for riots that have left an estimated 57 people dead and said it would foment further unrest unless its demands are met.

The previously unknown "Movement for Algerian Renewal" called for satisfaction of people's demands for more and cheaper food and for ousting the government, whose austerity policies helped cause the unrest.Interior Minister El Hadi Khediri announced late Saturday the "troubles" that began Tuesday with rioting in this capital had spread to the eastern port of Annaba and other unspecified cities.

According to estimates by doctors and families claiming the bodies of relatives, about 50 people died during the violence in Algiers, which started Tuesday night.

Some of the dead were victims of fires that gutted buildings in several neighborhoods of the capital, according to the reports.

At least seven other people died Friday in clashes between rioters and security forces in Algeria's second-largest city, Oran, diplomatic sources in Algiers said.

There were unconfirmed reports of deadly clashes in Algiers Saturday afternoon and evening.

Salvos of gunfire could be heard in the center of Algiers after the 10 p.m. to 6 a.m. curfew went into effect for a third straight night. It was not immediately clear whether these were warning shots or shootings.

Khediri, speaking on state-run Algerian radio, gave no details on the situation in Annaba or elsewhere, saying only he was persuaded "reason will prevail.

"The Algerian state is determined to use all means to reestablish calm," Khediri said.