Toothpaste alert! Airlines that are heading to Russia have been warned of possible toothpaste bombs. With the Olympics taking place in Sochi, the House Homeland Security Committee warned that terrorists could have explosives in toothpaste or cosmetic tubes on flight.

According to CNN, airlines flying to Russia received a bulletin about the possible threat. According to Rep. Michael McCaul, the bulletin said that officials believed that explosives might be used during flights or could be smuggled in to Sochi where the Olympics will start on Thursday.

The alert is specifically related to the start of the Winter games. The opening ceremony is on Friday. Sources say they are confident about the level of safety of Sochi and Olympic venues, but intelligence is getting increased tips about threats to areas outside of Sochi, like transportation hubs.

The toothpaste tube concern is focused on flights from Europe and neighboring Asian countries, partly because the United States doesn't have as much intelligence sharing with those countries.

U.S. intelligence is still trying to determine the credibility and scope of this specific threat. Russia and the U.S. have been exchanging intelligence information. To assess the credibility of this threat, officials have to look at the locations and the capabilities of known terrorists who make explosives and if they have the ability to build a toothpaste bomb. A device like that would require explosives that are hard to detect and contain hardly any metal content or things like a detonator.

Currently there is no known threat in the United States but intelligence says the threat is very real.

"It's real. It's real and we got very good information," a government source told CNN. "It's based on a credible source. We're taking it seriously. So are other countries. ..."

Most of the direct flights into Russia are coming from Europe and Asian countries. Very few originate in the United States.

Russian transportation officials are already taking caution and have banned liquids in carry-on luggage. Security officials in the US and Europe will be paying special attention to toothpaste and makeup.

"My prediction is that they will give a direct order that they'll be removing toothpaste from passengers' hand-carried items" and possibly from checked luggage as well,  Glen Winn, a former security director at United and Continental airlines told CNN.