Russian security officials are hunting down three potential female suicide bombers, one of whom is believed to be in Sochi, where the Winter Olympics will begin next month.
Police leaflets seen at a central Sochi hotel yesterday contain warnings about the women.
One of them, Ruzanna Ibragimova, a 22-year-old widow of an Islamic militant, is said to be at large in Sochi.
Police material distributed to the hotel staff also included pictures of two other women in veils: Zaira Aliyeva, 26, and Dzhannet Tsakhayeva, 34. It said they had been trained "to perpetrate acts of terrorism".
It warned that the two women "are probably among us" but, unlike in Ibragimova's case, did not say if they were in Sochi.
Russian authorities have blamed the so-called "black widows" of slain insurgents for previous suicide attacks.
Ibragimova reportedly was seen recently in Sovetskaya Street in downtown Sochi.
The police report contained an image of the search document signed by a local police chief that said Ibragimova also had a nickname, Salima. ABC News reported that she was the widow of an insurgent killed by police last year in Dagestan.
Ibragimova is described as having a large scar on her left cheek, a limp, and a stiffened left arm.
The scar was visible in photographs that showed a thin woman wearing a pink headscarf, with deeply set eyes. Other images that were reportedly included in the search document showed her to be fuller faced.
A Sochi news website said she arrived in Sochi 10 days ago.
Fox News said the Russian FSB security agency had distributed wanted posters featuring Ibragimova to American and other foreign security agencies last week.
"According to our information, Ms Ibragimova may be used by the ringleaders of illegal armed groups for the organisation of terrorist acts in the zone of the 2014 Olympics," the bulletin said.
"The notice is the first sign that terrorists may have managed to penetrate the security cordon," Fox cited a separate US security force bulletin as saying.
The report came less than a month after two suicide explosions rocked the industrial centre of Volgograd, 640 kilometres northeast of Sochi, killing 34 people and injuring dozens.
On Sunday, the radical Islamist website Vilayat Dagestan carried a statement by a rebel group commander taking responsibility for the attacks.
It included a 50-minute video in which two young men of Caucasus appearance, identified only as Suleiman and Abdurakhman, are seen allegedly preparing for the suicidal missions at Volgograd's railway station on December 29 and on a crowded bus in the city the next day.
In a televised interview aired Sunday, Russian President Vladimir Putin insisted that all necessary measures were being taken to provide security at the Sochi Games. About 40,000 police and security agents aided by troops were being deployed, he said.
Putin said the security measures "will be organised in such a way that they don't catch the eye and, so to say, don't depress the participants in the Olympic Games".
But the measures have already depressed some residents and construction workers in Sochi.
Natalia Kalinovskaya, deputy head of the city's ecology council, was awoken late at night last month by a loud knocking on the door.
"Two police officers told me I was on a list of suspicious persons and that they wanted to take me down to a police station to explain in writing what I was planning to do during the Games," said Kalinovskaya, who lives in the nearby village of Sovkhoz Rossiya, where the Olympic Village is situated.
"They said I was blacklisted for organising mass rallies of local residents in the past."
Kalinovskaya showed the officers her ID as a federal lawmaker's aide and they left her in peace, after asking her to show them the way to the apartment of her neighbour, an alleged drug addict.
Associated Press, McClatchy Tribune
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