MOSCOW - Moscow evacuated more than 10,000 people on Wednesday (Sept 13) from shopping centres, railway stations and universities, Russia's RT news website reported, after "almost simultaneous" warnings they had been rigged with explosives.

Twenty sites are currently being evacuated, with emergency services saying that specialist units and officers with sniffer dogs were examining the buildings.

The sites evacuated included the capital's biggest railway stations, more than a dozen shopping centres and at least one university, RT reported.

Three of the shopping malls have been cleared by authorities, the Tass news agency reported.

An emergency services source told Tass that more than 10,000 had been evacuated on Wednesday, although the exact number was still being confirmed.

"This appears to be a case of telephone terrorism, but we have to check the credibility of these messages," the source added.

Threats and evacuations were also reported in cities ranging from Petropavlovsk-Kamchatsky in the Far East, across Siberia, to Kaliningrad on the Baltic Sea, Bloomberg reported.

More than 45,000 people have been evacuated from airports, schools and government buildings across Russia over the last two days amid a wave of fake bomb threats that officials have called unprecedented, Bloomberg reported.

"There's never been anything like this before, it's 100 per cent organised telephone terrorism," Frants Klintsevich, deputy head of the Defence Committee in the upper house of parliament, said in a telephone interview.

"The only goal is to set off destructive processes, to sow panic. It's possible this could be preparatory work for a serious terrorist attack."

The official RIA Novosti news agency quoted an unnamed source in the security services as saying 45,000 people had been evacuated Tuesday from 205 buildings in 22 cities. Many were city halls, schools and other official buildings, according to local news reports. The Interior Ministry and Security Council declined to comment.

The anonymous calls came from Internet dialing systems and could not easily be traced, official news agencies reported. Initial reports indicated the evacuations might have been some kind of exercise. Klintsevich and other officials said the source could have been Ukraine.