An Interior Ministry officer stands guard inside the airport of Sochi, the host city for the Sochi 2014 Winter Olympics April 22, 2013. A group leading an Islamist insurgency against Russia said on Sunday it was not at war with the United States, distancing itself from last week's Boston Marathon bombing. Insurgent violence, rooted in two separatist wars between Russian troops and Chechen separatists following the fall of the Soviet Union, occurs regularly across the North Caucasus near Sochi, where Moscow plans to hold the 2014 Winter Olympics. REUTERS/Alexander Demianchuk (RUSSIA - Tags: TRANSPORT CRIME LAW CIVIL UNREST POLITICS SPORT OLYMPICS)