Hundreds of thousands of commuters were left without a service on the Tube yesterday thanks to signal failures and late engineering work on the worst day on the Underground this year.
The disruption, which saw five lines - virtually half the entire network - either closed or suffering huge delays, was described as "unacceptable".
Thousands were left stranded as the Jubilee, Metropolitan, Piccadilly and Bakerloo lines were all part suspended.
Jubilee line services - used by more than 650,000 passengers a day - were suspended between Willesden Green and Stanmore, with severe delays over the remainder of the route.
Trains did not begin running the full length of the Jubilee line until 12.30pm - more than seven hours after the scheduled start of service.
Commuters trying to switch to the Metropolitan line found that too suspended between Harrow-on-the-Hill and Aldgate. There were also delays on the Harrow-on-the-Hill to Amersham, Watford and Chesham lines. Transport for London said the chaos was the result of a late finish to weekend engineering work.
South London commuters also suffered as the Victoria line was hit with delays at the height of the morning peak due to signal failure at Brixton.
