Moscow mourns after blast kills 10
A militant Muslim group that claimed responsibility for the crash of two Russian airliners last week said it was also behind this latest attack.
Police promised heightened security on the sprawling city's transit system, one of the world's busiest and relied on by many of the city's estimated 10 million people. But the attack was only the latest in a string of violence in the capital and elsewhere that the government has appeared helpless to prevent.




