At least 37 people are reported to have been killed in two explosions on the Metro system in central Moscow.
The first blast happened at the city's central Lubyanka station killing 25, reports quoting security sources said.
A second explosion less than an hour afterwards happened at the Park Kultury station killing 12, Russian news agency Tass reported.
Ten people were injured in the first blast and 12 in the second, Tass said, quoting police and officials.
An emergencies ministry spokeswoman said that at Lubyanka 14 people were killed in the train and 11 on the platform.
"The blast hit the second carriage of a metro train that stopped at Lubyanka, at 0756 (0356 GMT)," Irina Andrianova said.
"There was no fire. Rescuers of the Moscow emergencies department and firefighters are now working at the site," she added.
The headquarters of the Russian Federal Security Service (FSB), is located just above the station.
The second blast came about 40 minutes later, at 0838 (0438 GMT).
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