The Transportation Security Administration is temporarily banning travelers from bringing any amount of liquid, gel or aerosol in their carry-on luggage aboard flights between the U.S. and Russia, following a warning from the Department of Homeland Security that terrorists could target the Olympic Games with explosive components hidden in toothpaste tubes.
"As always our security posture, which at all times includes a number of measures both seen and unseen, will continue to respond and appropriately adapt to protect the American people from an ever evolving threat picture," said a DHS official who confirmed the new liquid ban. "These measures include intelligence gathering and analysis, deployment of cutting edge technology, random canine team searches at airports, federal air marshals, federal flight deck officers, temporarily restricting certain items and more security measures both visible and invisible to the public."
Russia had banned travelers in their country from having any liquids or gels in their carry-ons last month, but until now American security had allowed a small amount to be taken aboard planes in the U.S. The items can still be packed in checked bags.
The new temporary restriction comes a day after the U.S. government sent to U.S.- and foreign-based airlines saying that extremists "may target aviation" with bomb-making materials hidden in toothpaste or cosmetic tubes as part of a broader effort to violently disrupt the Olympic Games in Sochi, Russia.
The notice said the potentially deadly strategy could be used for one of two ends: Either multiple terrorist operatives aboard a plane could assemble a device while in flight, or the attackers could just use the flight to smuggle the explosive components to another, unidentified destination.
ABC News first reported Wednesday that the Department of Homeland Security had issued the warning to airlines with flights to Russia. A DHS official on Wednesday declined to offer more details on the warning, but said the department "regularly shares information with domestic and international partners, including those associated with international events such as the Sochi Olympics." The official said the department was not aware of a threat to the American homeland.
The opening ceremony for the Sochi Games is scheduled for Friday, though the first official qualifying rounds began today.
While top U.S. lawmakers, including House Homeland Security Committee Chairman Michael McCaul, said the toothpaste tube threat is based on "very specific and credible information," several U.S. counter-terrorism officials stressed the complexity of intelligence gathering and said information on any specific threat -- no matter how likely to come to pass -- would be passed along to the effected parties.
Russia's top Olympic official appeared untroubled today by the toothpaste tube threat.
"All the information we have at this moment on threats and risks allows us to say that security at the Olympics will be provided," Russian Deputy Prime Minister Dmitry Kozak told reporters, according to Russia's state-owned RIA Novosti. Kozak, who is in charge of overseeing the Olympics, said that Russian authorities are making every effort to ensure the safety of athletes and spectators at the Games.
"I think you're going to see a tightening of the screening procedures on these types of items that could contain explosive devices, that could either be used to blow up an airplane going to Russia or be smuggled into the Sochi are for the Olympics," McCaul, R-Texas, said.
Frank Cilluffo, Director of the Homeland Security Policy Institute, said that even a "small amount of certain explosives can, in fact... do grave damage [to] an aircraft."
The same intelligence that prompted the warning also led to the arrest of two women in France and several other people in Austria, an official briefed on the situation said, though local media reports that in both cases the suspects were let go.
Security in Sochi has been high for months due to the threat posed to the Games by Islamic militants in the region.
Sochi lies on the Black Sea, just 300 miles away from the heartland of an Islamic militancy in the North Caucasus. Doku Umarov, the leader of the insurgents known to some as Russia's Osama bin Laden, told his followers last summer they should do what they can to disrupt the Games, which he called a "satanic dance" on the bones of their ancestors.
In the past three months, Russia has suffered three suicide bombings in southern cities attributed to the militants. In January the U.S. State Department urged its citizens traveling to Sochi to be "vigilant and exercise good judgment" during the Games because of the terror threat.
But Team USA has not been detered, U.S. Olympic Committee CEO Scott Blackmun said today.
"Any time you have an event on this scope and scale there are security threats. There are terrorism threats. What makes this one a little bit different, and frankly a little bit more concerning when you think about, is that someone has surfaced and levied an expressed threat. But it's not going to change the fact that the United States is going to show up and compete in these games and that their fans will be here," he said.
ABC News' Lee Ferran contributed to this report.