Preparations are underway at Russia's 2014 Winter Olympic stadium in Sochi.<br/> <br />The city is a few hundred kilometres from Russia's most restive North Caucasus provinces, which have always been considered a security risk.<br/> <br />There are now worries that the site in Russia's south could pose a security threat for the U.S. citizens following the Boston Marathon bombings, blamed on two men, whose family is from Chechnya - a largely Muslim North Caucasus region where Russian forces are fighting Islamic militants.<br/> <br />The organizers of the Games have refused to comment.<br/> <br />But an analyst from the Moscow Carnegie Centre Maria Lipman believes the threat is real.<br/> <br />(SOUNDBITE) (Russian) CARNEGIE MOSCOW CENTRE EXPERT MARIA LIPMAN, SAYING:<br/> <br />"If there are groups seeking to deal a blow on the United States in Dagestan and Chechnya or anywhere, then of course it (Olympics) is unsafe for Americans. And, of course, it would be a disaster for Putin personally who cared so much about wi
