Tube users were experiencing severe delays on the Central Line following the derailment of a train on Thursday.
Passengers were stuck inside the trains for about two hours
The line remains closed in both directions between Leytonstone and Liverpool Street, in east London.
A special bus service is running and Tube tickets are being accepted on buses and some mainline rail services.
Safety checks are under way on the Tube's storage facilities after a dislodged roll of tarpaulin landed on the tracks, causing the derailment.
Three carriages came off the rails on a westbound Central Line between Mile End and Bethnal Green during the morning rush hour.
Hundreds of passengers were stranded for up to two hours and 11 people needed hospital treatment.
Work continues to rerail the train and repair the damage and a full service is unlikely to resume until over the weekend.
Replacement bus services will run from Stratford to Leytonstone calling at Leyton, from Gants Hill to Ilford, Walthamstow Central to Woodford and Barking to Redbridge.