There are reports of several explosions during an anti-terror raid in Russia's second-largest city.
It's understood there were at least two explosions in a residential building in St Petersburg, which was surrounded by dozens of armed officers and police cars at around 10:30am (local time).
Local media say the 16-storey building was cordoned off by Russian National Guard and security forces, before explosions began sounding around an hour later.
Witnesses say the explosions were followed by plumes of smoke, with officers swarming the area after armed gangs were inside the building.
According to a correspondent from the Fontanka media outlet, a person on a stretcher was carried out of the building and loaded into an ambulance.
Three alleged militants, believed to be linked with illegal armed gangs in the North Caucasus region, have reportedly been arrested.