An Algerian government official says security forces have killed a dozen extremist fighters in northern areas outside the capital and uncovered an arms cache in an area known for attacks against security forces.

The official, who wasn't authorized to give the information publicly, said Saturday an army patrol killed eight extremists in Boumerdes, about 50 kilometers (30 miles) outside the capital, Algiers. The official said four fighters were killed in the northern Boukadir forest about 280 kilometers (175 miles) away.

Terrorist attacks have dropped dramatically in Algeria's populated north in recent years and are largely restricted to a small operations against local forces.

But President Abdelaziz Bouteflika said Saturday that fighting in neighboring Mali has raised the threat of "the terrorism that we never stop fighting."