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.
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In a tweet on Saturday, the US president didn't give a reason for his absence but said he wished"everyone well and have a great evening".
Weather conditions remain wet and windy through the weekend.
Mr Banks has given Ukip leader Paul Nuttall an "ultimatum", saying if he is not made chairman he will stop supporting the party.