Two explosions have hit the Moscow underground system, killing and injuring dozens of people in the middle of the morning rush hour.
More than 20 people were killed in the first blast just before 0800 (0400GMT) at Lubyanka station in the centre of Moscow.
About 40 minutes later, a second blast at Park Kultury station, also in central Moscow, killed another 12 commuters.
Many more were injured in that blast.
The explosion at Park Kultury took place at the back of the train as people were getting on board.
Police and emergency vehicles blocked Lubyanka Square, home to the headquarters of Russia's FSB security service, the successor to the Soviet KGB.
Early reports indicated both attacks were carried out by suicide bombers and Moscow Mayor Yuri Luzhkov told reporters both attackers were female.
While no group has yet said it carried out the bombings, previous suicide attacks in the Russian capital have been blamed on Islamic rebels fighting for independence for the Russian region of Chechnya.
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