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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Tonight, staying windy with gusty southwesterlies, remaining mild and mostly cloudy.
The notices have been posted in Covent Garden are thought to be aimed at organised criminal gangs.
A cloudy start to the short Christmas week. It's gong to be a mild one though with temperatures already above the double figure mark.