At least 30 people, including 20 police officers, were injured after a suicide bomber blew himself up during an anti-terrorist operation in Russia's volatile North Caucasus republic of Dagestan, police sources said.
"According to latest updates, 30 people, including 20 police officers, have been hospitalised after the blast," the source said, adding that three people were in serious condition.
"The terrorist attempted to break through a police cordon, but he was stopped by a policeman and set off the bomb. His identity is being established," the official said.
Police surrounded a group of militants in a private house in the Dagestani capital of Makhachkala on Friday evening. Two militants and two police officers were killed in the ensuing gunfight.
The special anti-terrorist operation has been suspended until Saturday morning as an unknown number of militants remain holed up in the surrounded building.