U.S. news network CNN is reporting that Russian police in next month's Olympics host city, Sochi, have distributed fliers showing a woman they believe could be a terrorist and currently in the city.
The station says it obtained a copy of the flier "from security staff" at a hotel in the Black Sea resort city.
The 2014 Winter Olympics are slated to begin in less than three weeks' time, on February 7.
Fears of a spillover of violence from a North Caucasus insurgency against Moscow loom large over the games.
Russian officials have vowed the Sochi Games will be safe, but the United States has issued a "travel warning" over the potential for terrorism targeting the event.
The Sochi police flier asks employees for help in locating Ruzanna Ibragimova, whom it describes as "the widow of a member of a militant group from the Caucasus," according to CNN
In a later report, NBC News
quoted U.S. and Russian sources as saying that authorities in Sochi are looking for as many as four "black widows," a reference to women whose husbands have been killed in the North Caucasus and who might be prone to carrying out attacks.
An Islamist militant group has claimed responsibility
for two suicide bombings that killed at least 34 people last month in the Russian city of Volgograd.
In a video posted online, "Vilayat Daghestan" (Daghestan Province) also threatened to attack the Olympics.
Russian authorities, including Chechen Republic head Ramzan Kadyrov, have suggested on multiple occasions that Chechen militant Doku Umarov, who has claimed numerous terror attacks in the past and threatened to target the games, is dead.
Those reports, however, have not been confirmed
The Pentagon said it has offered its "full support to the Russian government" for security preparations ahead of Sochi.
U.S. Navy Rear Admiral John Kirby, the Pentagon’s current press secretary, told journalists on January 20 that U.S. military commanders in the region are “conducting prudent planning and preparations” in case Russia needs support. Two U.S. Navy ships in the Black Sea “will be available if requested” and “in consultation” with Russian authorities, he said, adding that there have not been any requests for assistance from Russia so far.