Far-right organisation English Defence League has called on its supporters to gather in Woolwich to protest in response to today's attack.
Leading members have called for people to "take to the streets" and asked them to join a local division of the organisation.
One message, posted online, asked members to get to London "...now if possible."
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Tonight western and northern areas will remain a little breezy with a few showers at times.
Leicester are Premier League champions after Tottenham conceded a two-goal lead in a bad-tempered 2-2 draw at Chelsea.
Football fans and players from all over the world savoured Leicester City Premier League triumph on Monday night.