Airlines that will have flights to Russia have been warned about the possible use of toothpaste bombs, ahead of the Sochi Winter Olympics.

A federal law enforcement official source has said that they were told of the possibility of this type of bomb, but not whether it was feasible, reports USA Today. The official also noted that there hadn't been an actual threat yet, but comes from intelligence information that is constantly being monitored.

The Department of Homeland Security also released a statement, according to CNN, saying, "Out of an abundance of caution, (the DHS) regularly shares relevant information with domestic and international partners, including those associated with international events such as the Sochi Olympics."

A top U.S. counter-terrorism official, Matthew Olsen, told Congress on Tuesday that there are "specific threats" being examined for validation on whether they could actually be carried out, especially from certain Muslim fundamentalists in the nearby region.

Secretary of State John Kerry said that people shouldn't worry about going to the Winter Olympics. But beware, evidently the hotels haven't been all that impressive, with journalists and athletes publicly grumbling about their accommodations.

image: NBC