Sochi: 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 by an Associated Press reporter at a central Sochi hotel on Tuesday contain warnings about three potential suicide bombers. A police letter said that one of them, Ruzanna Ibragimova, a 22-year-old widow of an Islamic militant, was at large in Sochi.
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'Black Widows' heighten Olympic security
Russian security officials are hunting down three potential female suicide bombers, one of whom is believed to be in Sochi.
A US congressman who was in Sochi on Tuesday to assess the situation said he was impressed by the work of Russian security forces but he was concerned that potential suicide bombers had entered the city, despite the extraordinary security measures.
"We know some of them got through the perimeter," Michael McCaul, chairman of the US House Homeland Security Committee, said. "She's for real. What we don't know is how many more black widows are out there."
Russian authorities have blamed the so-called "black widows" of slain insurgents for previous suicide attacks in the country.
An Islamic militant group in Dagestan posted a video on Sunday threatening to strike the games in Sochi, about 500 kilometres west of Dagestan.
Mr McCaul, a Republican from Texas, said he had numerous meetings with officials in Moscow and Sochi, and was briefed by the joint operation centre in Sochi, which is responsible for overall security in the area.
"The one improvement I would ask of the Russians is to allow our intelligence services to co-ordinate and co-operate better with theirs," Mr McCaul said. Although the Russian side was confident that it could provide security, the US has information that could help keep the games safe, he said.
The congressman also expressed concern that terrorists could have entered Sochi before security was tightened.
"How many potential cells could be in Sochi and the Olympic village?" he said. "But after `the ring of steel' was implemented we have this one person who seems to have been able to penetrate it. It does demonstrate vulnerability."
Police material distributed to the hotel staff 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". No further information was provided about the two women or their motivation.
The term "black widow" refers to the belief that women who have carried out past suicide attacks in Russia did so to avenge the deaths of husbands or other male relatives.
Security officials in Sochi were not available for comment on Tuesday.
Russian President Vladimir Putin had a phone conversation on Tuesday with US President Barack Obama in which they discussed how best to have a "safe and secure" Winter Olympics.
The US military is making two ships in the Black Sea available should American support be required during the Olympics, and Washington is also offering US technology used to thwart roadside bombs, a spokesman for US Joint Chiefs of Staff chairman Martin Dempsey said.
Russian troops have been active fighting militants in Dagestan.
On Tuesday, troops shot dead the leader of a militant group, Interior Ministry spokeswoman Fatina Ubaidatova said. She said the militant, Eldar Magatov, was wanted in attacks on security forces, bombings and the extortion of businessmen.
Interior Ministry troops elsewhere in Dagestan defused an explosive device placed near a village administration building and engaged in a firefight with militants holed up in a house, the spokeswoman said.