U.S. reveals 'specific' threats to Olympics

U.S. officials say they have specific reasons to worry about security in Sochi, only three days before the Winter Olympic Games are set to open in the Russian city.Speaking at a House Intelligence Committee hearing on Tuesday, Matthew Olsen, director of the National Counterterrorism Center, highlighted concern over the Games and whether Muslim fundamentalists in disputed regions of Russia -- or other groups -- could launch deadly attacks on selected targets."There are a number of specific threats of varying degrees of credibility that we're tracking," he said."And we're working very closely with the Russians and with other partners to monitor any threats we see and to disrupt those."Russian security forces have cracked down on suspected militants in the restive North Caucasus republic of Dagestan and elsewhere in recent weeksafter twin suicide bombings in the city of Volgograd in December."The primary threat, from a terrorism perspective, comes from Imarat Kavkaz, probably the most prominent terrorist group in Russia. It's made its intent clear to seek to carry out attacks in the run-up to the Games," said Olsen. "We think the greater danger from a terrorist perspective is in potential for attacks to occur outside of the actual venues for the Games themselves in the area surrounding Sochi or outside of Sochi in the region."His comments were echoed by U.S. Rep. Mike Rogers, chairman of the House Intelligence Committee, who spoke to CNN's "Erin Burnett OutFront" Tuesday night."I think the venues themselves will be OK. The Russians have done a lot of guards, gates and gunsto try to secure the venues and try to get a ring around the Games. I'm very concerned by the sheer level of attention and effort, not just from Chechens and folks in that region, but outside of that region that have expressed an interest in actually having a violent act occur at the Games."He complained about cooperation issues."They're not at 100%. They really should be when it comes to peoples' lives at the Games, and we know that it's such a high-threat environment," said Rogers, R-Michigan.President Barack Obama was briefed Tuesday on U.S. efforts to support security in Sochi.