- Knowles, who walks with a limp, is 5ft 8in, heavily built and has tattoos on both arms and a scar across his left eye
- He was wearing a light grey tracksuit and a black cap when he was last seen
- People are advised not to approach Knowles but to call 999 if they see him
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Camden Council is evacuating five tower in the Chalcots estate in north London, to allow "urgent fire safety works" to take place.
Scotland Yard said it was taking action under public order laws over the marches "due to concerns of serious public disorder".
The Football Association says it is hoped that the match will raise around £1.25million for the victims.