Services on London Underground were disrupted for the ninth weekday in a row today because of late running engineering works which hit one of the capital's busiest Tube lines.
Passengers on the Victoria Line, used by over half a million people a day, had to switch to other routes or catch buses or overground trains.
LU said there were "severe delays" due to the late finish of engineering work at Highbury & Islington, advising Tube users that their tickets were being accepted on buses, National Express East Anglia and Southeastern trains.
The Victoria Line also suffered delays yesterday after passengers' bags were caught in the doors of new trains, with one train having to be taken out of service with a door defect and another temporarily withdrawn to have a window repaired.
A train was cancelled on the Metropolitan Line this morning because of "ongoing maintenance problems", passengers were told.
Thousands of passengers had to be led along tracks because of problems last week and disruption has continued every day this week.
Commuters face more chaos next week because of a strike by Tube workers from 5pm on Tuesday in a row over job losses.
Talks are being held at the conciliation service Acas in a bid to avert the walkout.
Bob Crow, general secretary of the Rail Maritime and Transport union said: "RMT stands ready and willing to talk, as it has from the start.
"If we are to make progress, London Underground must be prepared to talk seriously about the one thing it has so far refused to discuss, and that is the safety-critical jobs at the heart of this dispute."
Meanwhile, planned engineering works will lead to the closure of the entire Circle Line this weekend, closures on the Waterloo and City Line and partial closures of the District, Hammersmith and City, Jubilee and Metropolitan lines.