At least three people have been killed and 21 injured after a homemade explosive device was detonated at an Italian restaurant in Moscow, Russian state media quotes security officials as saying.

The blast happened at around 20:00 local time (17:00 GMT) on Kudrinskaya square near the city centre.

The National Anti-Terrorist Committee (NAK) said a woman carrying the explosives tried to enter the restaurant but was stopped by a security guard. The device detonated, killing the woman, the guard and a visitor to the restaurant.

The restaurant, located in one of Moscow’s famous Stalin-era skyscrapers, had been holding a private function.

Witnesses said they saw people being brought out covered in blood after the explosion.

Initial reports said the blast happened in the establishment’s kitchen but the restaurant later put out a statement saying everything was ok inside and that “there was a problem outside”.

Roads around the square were briefly closed. Dozens of cyclists had been gathering nearby for an evening ride through the city but the event was cancelled.

Video released by Russia’s RIA news agency showed heavily armed law enforcement officers at the scene, which had been closed off to members of the public.