A series of hoax phone calls triggered mass evacuations of various sites around the Russian capital.
More than 15,000 people were evacuated on Wednesday from several shopping centres, universities and train stations in Moscow after a series of bomb threats, Russian media reported.
A source in the emergency services told state-run TASS news agency that over 30 prominent locations including the famed GUM shopping centre on Red Square were temporarily emptied after anonymous telephone threats.
Interfax news agency cited a source as saying that over 15,000 people around the sprawling city were evacuated.
Neither the emergency services in Moscow nor the police could immediately confirm the incidents to AFP.
A representative for GUM told AFP that employees had been allowed back inside the building.
The spate of threats came after two days of similar calls caused disruptions in cities across Russia, with the state-run RIA Novosti news service reporting some 45,000 people were evacuated nationwide.
No bombs were found at any of the locations.
Kremlin spokesman Dmitry Peskov on Wednesday said the country's intelligence services were investigating the threats.