Hundreds of traffic jams have been reported in London tailing back nearly 200 miles-long, as commuters faced chaos caused by striking tube workers.
London Underground ground to a halt last night and will not return to normal until Friday morning, forcing commuters and tourists to walk or cram on to packed buses.
Members of four unions are taking industrial action for the second time in a month because of a deadlocked dispute over plans to launch the all-night Tube service next month.
Extra buses, Sanatander Cycles and riverboat services were all laid on in a bid to keep the capital moving, but it was not enough to mitigate huge disruption, with a surge in people driving to work.
At 8.45am on Thursday there were 428 separate traffic jams causing 197 miles of tailbacks, according to traffic experts at TomTom.
The total figure was double that of the same time last week, although less than last month's Tube strike, when there were 1,445 jams and 761 miles of delays.
The most congested roads were around Parliament Square (delays of 48 minutes) and on the A40 from Wood Lane to Marylebone Road (30 minutes).
"With many Londoners away on holiday and no school runs, the roads were not as congested this morning as they were during the last strike four weeks ago," a TomTom spokesman said.
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The dispute over pay and conditions for the planned night Tube has worsened in recent days, with more workers being balloted for action and London's mayor making it clear no more money will be offered.
Aslef general secretary Mick Whelan said: "Our members have rejected the latest offer from the company because they are forcing through new rosters without agreement and offer no firm commitments on work/life balance for train drivers."
RMT leader Mick Cash also spoke out in light of Thursday's 24-hour strike, saying: "The offer tabled by London Underground is just a rehash of an earlier package and does nothing to tackle the fundamental issue of our members being called into work at the beck and call of management to plug staffing gaps in the mayor's botched night Tube plans."
But Steve Griffiths, London Underground's chief operating officer, claimed union negotiators had rejected an "extremely fair offer".
"I am sorry that the unions have rejected our extremely fair offer outright and that the journeys of our customers will be disrupted today," he said.
"We have a volunteer army of hundreds on hand to help London's workers, residents and visitors get around during the strike. I thank customers for their patience as they make their journeys today."
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