MOSCOW, Nov 28 (Reuters) - A bomb caused the derailment of a Russian high-speed train that killed dozens and injured 100 others, officials said on Saturday, raising fears of a new bombing campaign targeting the Russian heartland.
The attack on the luxury Nevsky Express on Friday night on the busy main line between Moscow and St Petersburg was the worst attack outside the turbulent North Caucasus since a string of suicide bombings by Chechen rebels ended five years ago.
The following are details on what is at stake and who could be to blame:
WHO IS TO BLAME?
Most major attacks in Russia in recent years have been blamed on Islamist rebels from the North Caucasus who oppose Moscow’s rule and want to impose Islamic law.
But no group has yet publicly claimed responsibility for Friday’s attack.
Extreme Russian nationalists were initially blamed for an a similar explosion in August 2007 that derailed a Nevsky Express train on the same route, injuring 30 people.
Prosecutors later arrested two residents of the mainly Muslim North Caucasus region of Ingushetia, but said the mastermind behind the attack was ex-soldier Pavel Kosolapov, a former associate of late Chechen rebel commander Shamil Basayev.
A train filled mainly with middle-class ethnic Russians would be an unusual target for Russian nationalists, who have never carried out an attack on this scale before.
The discovery of bomb fragments appeared to rule out initial concerns that the crash was an accident caused by ageing infrastructure.
DID ISLAMIST REBELS PLANT THE BOMB? Militant groups from the North Caucasus would be more than capable of carrying out such an attack, said Grigory Shvedov, editor of the online journal www.Caucasianknot.info , which tracks violence in the North Caucasus.
But the distance from the North Caucasus and the complexity of designing a bomb to derail a high-speed train make the Nevsky Express an unusual target for groups who have in the past preferred simpler suicide bombs, he said.
On the other hand, a luxury high-speed train taking businesspeople and government officials home from Moscow on a Friday night would make an attractive target for Islamist rebels seeking maximum media exposure.
A claim of responsibility from the rebels would not necessarily settle the matter as such claims have often proved false in the past.
Chechen rebels claimed responsibility last August — through the unofficial Islamist rebel website www.kavkazcenter.com — for a Siberian dam disaster that killed 75 people. But most observers dismissed the claim.
COULD THIS BE THE START OF A NEW CAMPAIGN?
The last major attack to hit Russia’s historic heartland was in 2004, when a string of suicide bombings targeted planes and metro stations in Moscow.
A surge in violence in Chechnya and Ingushetia this year prompted some analysts to predict a new wave of attacks on the capital. Russian media reported in September that well-prepared suicide bombers planning an attack on Moscow had been arrested in Chechnya.
An attack deep inside Russia’s heartland would mark a sharp change in tactics. If such a decision has been taken, further attacks would be likely, Shvedov said. A new campaign would likely be announced publicly, he said.
WHAT DOES THE ATTACK MEAN FOR RUSSIA?
A new wave of Islamist attacks against targets in Moscow and other major cities would have unpredictable results, stoking fears about political stability and possibly spooking Russia’s stock, bond and currency markets.
Prime Minister Vladimir Putin is credited with helping to bring Chechen rebels under control when he was president from 2000 to 2008, so a new wave of attacks would undermine that achievement.
"This is actually a very serious political blow to the present Russian regime," said Pavel Felgenhauer, a defence commentator for the opposition Novaya Gazeta newspaper.
A series of high-profile attacks could force the government to launch military operations against suspected rebels, a move that would increase tensions in the already turbulent regions. (( For the main story on the crash, click on [nGEE5AR00F] )) (Writing by Conor Humphries; Editing by Kevin Liffey) ((email@example.com; +7495-7751242))