The Department of Homeland Security issued a warning for airlines flying into Russia for the Winter Olympics. The US warned that explosives could be hidden in toothpaste tubes that are smuggled on to planes.
They went on to say that there was no specific danger to the US at this time.
This is the latest reported threat concerning the winter games in Sochi, where security has been increased.
The Department of Homeland Security said in a statement to the BBC that it «regularly shares information with domestic and international partners, including those associated with international events such as the Sochi Olympics».
As a result of the increased security concerns for these games, the US has placed two warships in the Black Sea in the event of a security threat. Fear has been mounting following two suicide attacks in Volgograd in December, and numerous threats from Islamist militants in the Caucasus region.