A police statement warning those who would provoke trouble at a vigil being held by Mark Duggan's family follows concerns that the crowds would clash with football fans going to see Tottenham Hotspur play Crystal Palace, but the match is set to go ahead at 3pm.
On Thursday Britain's most senior police officer and Prime Minister David Cameron both urged supporters to remain calm at the vigil.
The commissioner of the Metropolitan Police, Sir Bernard Hogan-Howe, thanked the Duggan family for their public calls for peace.
He said: "A vigil is to commemorate Mark Duggan's death, that's what the vigil is about."It's a terrible tragedy that someone's lost a life in this case, and clearly the family want to register, I believe, their protest about the outcome of the inquest."
More top news
Mladic, now 75, was the military commander of Bosnian Serb forces in the 1990s, who fought against the Bosnian Croat and Bosniak armies.
Weather: Heavy rain and strong winds in the north
His representatives said Cassidy, who was hospitalised last week, died "surrounded by those he loved."