Russia orders terror probe as rail explosion kills 26

Russian authorities have begun a criminal investigation into a suspected terrorist bomb attack that derailed a luxury train en route from Moscow to St Petersburg on Friday night, killing at least 26 people and injuring about 100.

It was the largest such attack in Russia for five years, and the prevailing version in the Russian media is that the bombers could be linked to Islamic extremist groups operating in Russia's troubled north Caucasus region. No one has claimed responsibility for the blast.

Vladimir Markin, a spokesman for the investigative committee of the Russian general prosecutor's office, said the incident was a terrorist attack, but it was "too early to speak about suspects".

But Ren-TV reported that investigators were searching for a group of men who had been staying in a town near the site of the blast. "Investigators say the bombers left much evidence behind," a programme on the Russian channel said.

Alexander Bortnikov, head of Russia's Federal Security Service, said investigators had found pieces of a trackside bomb that detonated with the force of about seven kilograms of TNT.

The last big terrorist attack in Russia was in August, when a suicide bomber drove a lorry full of explosives into a police station, killing 21 people, in Nazran, the capital of Ingushetia, in the north Caucasus.

An Islamic extremist group based in Chechnya and linked to the warlord Doku Umarov was apparently behind an attack in August 2007 that targeted the same train on the Moscow-St Petersburg route, according to a statement by the prosecutor's office. That attack derailed the train but caused only injuries.

Vladimir Yakunin, head of Russian railways, defended the response of the emergency services to Friday's blast, in a remote area. "Our trains are adequately equipped and our conductors go through special training," he said.

"The emergency services arrived after one hour, and the locomotive [crew] and conductors performed first aid at the scene."