Ilyas Saidov, from Russia's largely Muslim republic of Dagestan in North Caucasus, was one of a group of militants who attempted the terrorist attack. He was arrested as he fled Moscow after the explosives to be used accidentally detonated in a Moscow hotel, the Russian news agency RIA Novosti reported Wednesday.
Saidov's role in the plot was to monitor the transport of the explosives, investigators said, noting he cooperated during the inquiry.
Insurgents from the North Caucasus region have attacked Moscow in several incidents, notably in January 2011, when 35 people were killed in an airport suicide bombing, the news agency said.
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