At Euston fire station drivers in lorries, cars and taxis sounded their horns in support of the firefighters. The union's own fire engine was driven onto the station forecourt, with Johnny Cash's Ring of Fire song blaring from a loudspeaker:
We have been receiving a lot of public support today at picket lines across London.
There is solid support for the strike - but it is a sad day in some respects because firefighters don't want to be on strike.
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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.