'Suicide bomber' hits Russia's Volgograd train station
A female suicide bomber has been blamed for killing 15 people and leaving dozens more injured at a railway station in the southern Russian city of Volgograd.
Police identified the bomber as a Dagestan national called Oksana Aslanova - who had been married to two Islamists killed by Russian forces.
She apparently detonated a bomb in front of a metal detector inside the main entrance of the station. Russian television is suggesting there may have been two attackers.
Russian President Vladimir Putin ordered law enforcement agencies to take "all necessary measures".
Federal police spokesman Vladimir Kolesnikov said security would be stepped up at train stations and airports.