MOSCOW - Russian security forces shot dead two senior rebel leaders and several followers in separate operations in southern Russia, the Federal Security Service (FSB) said in a statement on Sunday.

The statement, faxed to Reuters, said Marat Kurbanov, known as the Emir of Dagestan, was shot dead along with two junior rebels on Saturday night outside the village of Shamkhal in Dagestan as the trio were transporting explosives in a car., a website which has links to the Islamist rebel movement, said three people in a car were killed on Saturday night but it was not clear who they were.

Russia is fighting an escalating Islamist insurgency in the North Caucasus, particularly in Dagestan, Ingushetia and Chechnya, and President Dmitry Medvedev has called the upsurge in violence the country's biggest domestic political problem.

The FSB said Kurbanov had been appointed Emir of Dagestan by rebels after his predecessor Umalat Magomedov was killed in December under similar circumstances.

It said the information received during Saturday's raid had helped its agents identify a hideout of another senior insurgent, Madrid Begov, a Russian special police soldier who defected and had turned against the authorities.

The FSB has said security forces neutralized Begov after storming a private house in Dagestan's capital of Makhachkala on Sunday morning.

The Kavkazcenter website also mentioned a firefight in a house in Makhachkala on Sunday morning and said one mujahideen was reportedly killed but it did not identify the dead fighter.

On January 6 a suicide bomber killed seven policemen and wounded another 20 people in Dagestan by detonating a car packed with explosives at a traffic police depot. After the attack President Medvedev said the bandits should be eliminated.

(Writing by Gleb Bryanski; Editing by Michael Roddy)