Female suicide bombers blamed in Moscow subway attacks

Russian investigators combing two subway stations attacked by female suicide bombers think Chechen rebels may have been behind the rush-hour strike that killed dozens of people.

"Our preliminary assessment is that this act of terror was committed by a terrorist group from the North Caucasus region," Alexander Bortnikov of the Federal Security Service said of the investigation at one of the blast sites.

"We consider this the most likely scenario, based on investigations conducted at the site of the blast," Bortnikov said. "Fragments of the suicide bombers' body found at the blast, according to preliminary findings, indicate that the bombers were from the North Caucasus region."

Prime Minister Vladimir Putin said the "terrorists" responsible for the Moscow subway attacks Monday "will be destroyed."