Washington (CNN) - The United States is advising airlines with direct flights serving Russia to be aware of the possibility that explosive materials could be concealed in toothpaste or cosmetic tubes, the chairman of the House Homeland Security Committee said Wednesday night.
Rep. Michael McCaul said the Department of Homeland Security issued a bulletin to airlines flying into Russia warning of the potential threat.
The bulletin, the Texas Republican said, indicated that officials believed the explosives might be used during flights or smuggled into the city of Sochi, where competition at the Winter Olympics begins Thursday. The opening ceremony is Friday.
A U.S. law enforcement official told CNN that the cause for the Homeland Security alert was specific to the imminent start of the Games.
A top U.S. counterterrorism official says there are "specific threats" aimed at the Olympics with just three days away.
The United States is currently tracking the threats and racing against time to stop any terrorist attacks.
U.S. warships and aircraft are moving into final position, ready to respond if needed.
President Obama was briefed on security and assured by his team that they are "taking all appropriate steps regarding the safety of Americans," the White House said.
During a high-level briefing in the Situation Room, Obama directed his team to continue to work closely with the Russian government and "to review carefully and act on any new information that might affect the security of the Games."
OutFront: Congressman Mike Rogers, the Chairman of the House Intelligence Committee.
U.S. athletes arrived in Sochi Friday ahead of the 2014 Winter Olympic Games.
All in all, there are 230 members of the U.S. team, making it the all-time largest delegation of any nation at the Winter Games.
Among them is the first-ever U.S. Olympic female ski jumping team.
But getting to this point was an uphill battle for these ski jumpers.
CNN's Ted Rowlands is OutFront with their inspiring story.