A "female suicide bomber" has been blamed for an explosion at a train station in southern Russia which has killed at least 13 people.

The country's National Anti-Terrorism Committee issued a statement following the attack at the central railway hub in the city of Volgograd.

The blast occurred at around 12.45pm local times (8.45am GMT), and footage from the scene showed bodies laid out next to ambulances outside.

A spokesman for the nation's top investigative committee said 13 had been confirmed dead so far, though that figure was expected to rise. The Volgograd health department told reporters several dozen people had been injured in the blast.

No group has claimed responsibility for the attack, which comes two months after another female suicide bomber blew up a bus in the same city, killing six and injuring around 30.

Officials said the attacker in that incident came from Dagestan, where Islamist insurgent activity has grown since the two separatist wars in Chechnya.

Today's bombing also comes several months after the Chechen rebel leader Doku Umarov issued a warning of attacks on the 2014 Sochi Winter Olympics.

There are heightened concerns about terrorism ahead of February's events in the Black Sea resort, some 600 miles south-west of Volgograd.