An official said it has information “specifically targeting flights to Russia”, where the Winter Olympics will begin in the resort city of Sochi Friday.
In a statement, the Department of Homeland Security Wednesday said “out of an abundance of caution”, it regularly shares relevant information with partners both at home and abroad.
“While we are not aware of a specific threat to the homeland at this time, this routine communication is an important part of our commitment to making sure we meet that priority,” it said.
“As always, our security apparatus includes a number of measures, both seen and unseen, and DHS will continue to adjust security measures to fit an ever evolving threat environment,” it said.
Security at the February 7-23 Games has been a major concern for Washington following two deadly suicide attacks in Volgograd.
Adding to the concern is a stream of threats from Islamist militants in the volatile northern Caucasus region.
Earlier Wednesday, officials said two US warships had arrived in the Black Sea and will stand ready to offer assistance in the case of a security emergency at the massive sports event.
Meanwhile, the Russian government said it was doing everything possible to make sure the Sochi Games are as safe as possible.
Dmitry Kozak, a Russian deputy prime minister, said, “We can guarantee the safety of the people as well as any other government hosting a mass event (can).”