Russian train toll hits 26

Police have released a composite sketch of a man thought to be involved in bombing the Moscow-to-St Petersburg train and the death toll from the horrific derailment rose to 26.

Authorities say Friday night's derailment of a train speeding from Moscow to St. Petersburg was caused by a bomb planted on the tracks. The blast gouged out 1.5 metre crater and sent the final three carriages of the 14-car Nevsky Express hurtling off the rails.

Health Minister Tatyana Golikova said a woman injured in the derailment died late on Sunday in a Moscow clinic, bringing the death toll to 26, three Russian news agencies reported.

Dozens of people were treated at hospitals for their wounds, some flown into Moscow and St. Petersburg by helicopter.

Russia mourned the train victims on Monday, with many entertainment events postponed or cancelled.

No suspects or motive have been named, but police released a computerised sketch on Monday of a possible suspect. It was not clear, however, if the black-and-white composite depicted the man whom Interior Minister Rashid Nurgaliyev had spoken of earlier, a man about 40 years old with red hair.

The business daily Kommersant cited an unnamed police source as saying authorities suspect the latest bombing involved the same criminal group linked to an almost identical attack on the same track in 2007. The 2007 attack injured dozens in the train that passed over; the motive went unexplained.

The Moscow-St.Petersburg train line is very popular with Russian business executives and government officials.

Two suspects in the 2007 blast were detained but a third, Pavel Kosolapov, a former military officer believed to have links to Chechen separatists, remains a fugitive.

Meanwhile, a small explosion early on Monday harmed a section of railroad track in the volatile North Caucasus republic of Dagestan. There were no injuries and a train passing at the time was unaffected, local transport police spokesman Akhmed Magomayev told The Associated Press.

Terrorism has been a major concern in Russia since the 1991 collapse of the Soviet Union, as Chechen rebels have clashed with government forces in two wars and Islamist separatists continue to target law enforcement officials.