Interior Ministry officers keep watch while people pass by at Kuznetsky Most metro station in Moscow March 29, 2010. At least 37 people were killed and 33 wounded on Monday when suicide bombers detonated explosives on two packed Moscow metro trains during the morning rush hour, the worst attack in the Russian capital for six years, officials said. The blasts took place at Lubyanka and Park Kultury metro stations. [Agencies]