NOVGOROD, Russia (Reuters) - Two men from Russia's turbulent Ingushetia region were sentenced to four and 10 years in prison on Friday over the 2007 bombing of an express train linking the country's two major cities, which injured 30 people.
The bomb derailed the Nevsky Express on Aug 13, 2007, half-way along the popular Moscow-St Petersburg route, near the city of Novgorod about 540 km (335 miles) northwest of the capital.
Prosecutors said the mastermind of the 2007 attack, Salambek Dzakhkiev, was given 10 years for "banditry", while Maksharip Khidriev received four years for "transporting explosives".
Arrested and jailed on suspicion of taking part in the bombing in October 2007, they were acquitted on Friday of the original charges of "terrorism". Those who actually carried out the attack are still at large.
Dzakhkiev and Khidriev, who are both 41, denied any involvement in the bombing.
On hearing the verdict, grey-haired Dzakhkiev cursed at prosecutors before saying: "Why sentence people to 10 years in a prison when they're not even guilty?"
Unconfirmed media reports say the man who ordered the attack was Pavel Kosolapov, an active member of the insurgency, which aims to create a pan-Caucasus, sharia-based Muslim state independent from Russia.
The Nevsky was also blown up in November 2009, killing 26 and injuring 100, in an attack claimed by Chechen rebels who form part of an Islamist insurgency simmering along Russia's south in the North Caucasus region that includes Ingushetia.
The beginning of the year has seen little let-up in violence in the North Caucasus, which Russian President Dmitry Medvedev has named the country's biggest domestic political problem.
Last week the Kremlin chief vowed to mercilessly eliminate "bandits" in the North Caucasus after a suicide bomber rammed a truck full of explosives into a police station, killing at least seven and wounding dozens.
Writing by Amie Ferris-Rotman, editing by Peter Millership