Police have defused three explosive devices...

Police searched the area near the building after a shootout with militant late last night. No casualties were reported among police or attackers.

But one explosive device detonated during the search, and three local residents were taken to hospital with concussion. The blast also caused a blaze at a natural gas pipeline, which was quickly put out, an official said.

"Three other explosive devices were discovered in the area and rendered harmless," an official said.

Attacks on police and authorities have been an almost daily occurrence in Ingushetia, one of Russia"s poorest regions. The neighboring North Caucasus republics of Chechnya and Dagestan have also been plagued by violence blamed on Islamic militants and criminal groups.

ROSTOV-ON-DON/MOSCOW, February 25 (RIA Novosti)