President Vladimir Putin has ordered tighter security from law enforcement agencies after a second bomb exploded in the country in just three days.
A female suicide bomber blew herself up in the entrance hall of a Russian train station on Sunday, killing at least 13 people in the second deadly attack in the space of three days as the country prepares to host the Winter Olympic Games.
The state investigative committee said the bomber detonated her explosives in front of a metal detector just inside the main entrance of Volgograd station. TV footage showed a massive orange fireball filling the hall and smoke billowing out through shattered windows.
"People were lying on the ground, screaming and asking for help," witness Alexander Koblyakov told Rossiya-24 TV.
A spokesman for Russian investigators said at least 13 people had died, although the regional governor put the toll at 15.
President Vladimir Putin ordered law enforcement agencies to take all necessary measures to ensure security, RIA news agency quoted his spokesperson as saying. A federal police spokesperson, Vladimir Kolesnikov, said security would be stepped up at train stations and airports.
Russian Heath Ministry spokesperson Oleg Salagai said 42 people were wounded and that some would be flown to Moscow for treatment.
Volgograd is a city of around one million people, about 690km northeast of Sochi, where the Winter Olympics – a major prestige project for Putin – will begin on February 7.
Formerly known as Stalingrad, it lies close to Russia's North Caucasus, a strip of mostly Muslim provinces plagued by near-daily violence in a long-running Islamist insurgency.
Insurgent leader Doku Umarov, a Chechen warlord, urged militants in a video posted online in July to use "maximum force" to prevent Putin from staging the Olympics.
An attack by a female suicide bomber killed seven people in Volgograd on October 21. On Friday, a car bomb killed three people in the southern Russian city of Pyatigorsk, 270km east of Sochi.
The station was busier than usual, with people travelling home for the New Year holidays. TV footage showed emergency services carrying out victims, with at least one body lying motionless on the ground.
Another witness, Vladimir, said: "I saw melted, twisted bits of metal, broken glass and bodies lying on the street."
Sunday's attack was the deadliest to strike Russia's heartland since January 2011, when Islamist insurgents killed 37 people at a Moscow airport. – Reuters