MOSCOW, January 17 (RIA Novosti) - Reports...

Anti-terrorism policing was stepped up in the Moscow Metro, and the FSB's regional departments throughout Russia were put on high alert to forestall any attacks.

Security was also reinforced at especially important military and state facilities, natural gas and oil companies. Organized trips of schoolchildren on public transport have been canceled until further notice.

Sintsov said anti-terrorism squads remained on high alert.

Two bomb explosions in Moscow's metro system in 2004 killed a total of 49 people and injured more than 300.

A bomb detonated in a train carriage between the central metro stations Avtozavodskaya and Paveletskaya in February, and in August another went off near the entrance to Rizhskaya station in northern Moscow.