Twenty-six members of a terrorist group, which derailed a passenger train in Russia last year, have been killed, chief of Russia's Federal Security Bureau (FSB) said Tuesday.

And 14 members of the group were arrested, Alexander Bortnikov told the National Counter-terrorism Committee.

Last November, a passenger train en route from Moscow to St. Petersburg was derailed on the border between Tver and Novgorod regions, some 400 km northwest of Moscow, killing at least 26 people and injuring nearly 100 others.

"More than 170 militants and their accomplices have been detained since the start of the year, and 10 terror attacks have been prevented," the Interfax news agency quoted Bortnikov as saying.

"Over 150 kg of explosives and 100 improvised bombs have been seized from militants," he said.

Bortnikov also revealed that investigators have identified those believed to be behind last month's Moscow metro suicide blasts and an attack in the town of Kizlyar in the North Caucasian republic of Dagestan.

The metro bombings killed 40 people and injured more than 100. Two days later, 12 people, including nine police officers, were killed in two suicide blasts in Kizlyar.