London commuters have been hit with rush-hour chaos as large sections of the Elizabeth line have been shut down.
Services have been suspended while the network deals with a major signal failure.
Trains on the Elizabeth line have stopped running between Abbey Wood and London Paddington.
Services are also suspended between Stratford and Whitechapel.
There is a fault with the signalling system between those two stations.
National Rail said the disruption is expected to continue until 7pm today.
Although there are Elizabeth line trains scheduled for later in the afternoon, commuters have been advised to seek alternative routes.
Tickets will be accepted on London buses, the Underground, Greater Anglia trains between Shenfield and London Liverpool Street, Southeastern rail between Abbey Wood and London Terminals and on Thameslink between Abbey Wood and Farringdon.
Trains between Shenfield and London Paddington will begin and end at London Liverpool Street.
Passengers travelling to central London have also been advised to go to Liverpool Street Station and change for an Elizabeth line train.
These commuters can also change at Stratford and use the Central or Jubilee Line, National Rail said.
Engineers are reportedly en route to fix the signalling issue between Stratford and Whitechapel.
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