Over 20 shopping centers, railway stations and universities had to be evacuated in Moscow, following warnings that they had been rigged with explosives.
All alerts have proved to be hoaxes and the authorities have urged the public to stay calm, the BBC said yesterday.
Interfax news agency cited a source as saying that over 15,000 people around the sprawling city were evacuated.
Over the past several days, thousands of Russian citizens have been evacuated following a wave of anonymous bomb threats that turned out to be false.
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Many were city halls, schools and other official buildings, according to local news reports.
The Interior Ministry and Security Council declined to comment.
Police said that phonecall threats were still coming in.
"Each call is being checked".
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Sniffers dogs are searching the areas to confirm if there is any truth to the threats made.
Three of Moscow's main train stations were being checked on Wednesday, along with the city's famous GUM department store near Red Square, and more than 20 other buildings, the news agency said. Social media accounts show bemused crowds milling passively outside evacuated buildings, and there have been no reports of disturbances of public order.
RIA cited its source as saying that numerous hoax calls may have been made from Ukraine.
"There is reason to assume this was all organised overseas", an official in Chelyabinsk, a city in south- west Russian Federation, told Interfax news agency.
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Major Russian cities have been targeted in previous bomb attacks, most recently in April, when a Russian citizen from the former Soviet state Kyrgyzstan detonated a bomb inside a St Petersburg metro train.