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While most Russian observers regard Muslim militants from the North Caucasus as the major source of terrorism, a new threat is emerging: Russian extremist nationalists, who are carrying out an increasing number of attacks.

The most recent was the November 27, 2009, Nevsky express bombing that killed 20 people and injured 100. Russian nationalists claimed responsibility, although subsequently Chechen militant leader Doku Umarov's Islamists said it was their work.