Russian media is reporting a man has shot dead a policeman and taken pupils hostage at a school in Moscow's north west.
The gunman is reportedly holding 20 pupils - under the age of15 - but has so far not made any demands.
More top news
Syria's ambassador to the UN told ITV News: "We are not killing our own people. We are fighting terrorists, this is the government's duty."
On the cusp of the coldest spell of the winter
Artists have been arriving at the Brit Awards carrying or wearing white roses as part of the anti-sexual harassment movement Time's Up.