An Algerian official says that security forces have killed 21 armed Islamic extremists who were meeting in a forest to plan an attack on the Algerian capital.

The official said that two others were captured in the assault Tuesday on the group meeting in the Boukram forest in Boumerdes, some 20 kilometers from Algiers. A dozen Kalashnikovs, three rocket launchers and dozens of homemade bombs were recovered.

It was the deadliest assault on extremists in recent times in Algeria where al-Qaida in the Islamic Maghreb carries out sporadic attacks east of Algiers.

The official, in the gendarmerie's command post in Boumerdes, said intelligence sources had informed the army of the meeting. He spoke on condition of anonymity because he was not allowed to speak publicly about the operation.