Chechen rebel leader Doku Umarov has said his group were responsible for Monday's double suicide bombings in Moscow.
Umarov is one of the last remaining original leaders of the Chechen rebellion that began in the early 1990s.
Russia's most wanted rebel leader also said that further attacks on the Russian heartland would follow.
In his video statement recorded on Monday, he said the attack was to avenge ‘the massacre by Russian invaders of the poorest residents of Chechnya and Ingushetia, who were picking wild garlic in the Arshty village on February 11, 2010, to feed their families.’
He also warned of fresh strikes against Russia, saying 'war will come to your streets, and you will feel it with your own lives and skins.'
Doku Umarov said Russians could no longer ‘idly watch the war in the Caucasus on their TV sets, watch it quietly, with no reaction to excesses and crimes committed by their gangs, which are being sent to the Caucasus under the leadership of Putin’.
It was the first claim of responsibility for Monday's metro bombings in Moscow that killed 39 people. The authenticity of the video could not be independently confirmed.
Unconfirmed reports have the two suicide bombers arrived in Moscow from the Caucasus by bus early Monday.
Prime Minister Vladimir Putin yesterday ordered security forces to snare the masterminds of the metro bombings, saying they should be scraped out from the sewers.
Separately, suspected suicide bombers have killed at least 12 people in Russia's North Caucasus, two days after similar attacks in Moscow.
The coordinated attack in the town of Kizlyar in Dagestan, neighbouring Chechnya, was the latest outbreak in a surge of violence in the Caucasus.
Russian Prime Minister Vladimir Putin said a single group could have been behind the bombings in Moscow and Dagestan.
'Yet another terrorist act has been committed. I do not rule out that it is one and the same gang acting,' Mr Putin told a government meeting, calling the attacks 'a crime against Russia'.
He ordered Interior Minister Rashid Nurgaliyev to bolster the police presence in the North Caucasus.
A suicide bomber dressed in a police uniform set off the second of two blasts in Kizlyar, which killed the town's police chief and several other officers, regional police and prosecutorial officials told Reuters.
The bomber pushed his way into a crowd of police and onlookers drawn by a massive car-bomb blast, officials said - a common tactic of North Caucasus insurgents, who have been attacking law enforcement authorities almost daily.
A police official said a black four-wheel-drive vehicle had exploded after traffic police tried to stop it, indicating a suicide bomber had been behind the wheel.
