Two policemen and two armed extremists were killed in recent clashes in Algeria, press reports said yesterday. The policemen died Thursday in a machine-gun attack on a roadblock in the Bouira region, 120 kilometers southeast of Algiers, in which two of their colleagues were also wounded. The previous evening two gunmen were shot dead by security forces during a search operation in Boumerdes region, 50 kilometers east of the capital. Weapons and ammunition were captured in the operation against the Salafist Group for Preaching and Combat (GSPC).