A signalling fault has plunged trains to and from Stansted Airport into chaos.
CrossCountry, Greater Anglia and Stansted Express services are all affected with passengers travelling to and from the airport facing major disruption until at least 8.15pm.
It comes as delays are easing to rail services from King’s Cross after a person was hit by a train.
The incident shut lines between London and Stevenage but they have now reopened, with some disruption still expected until 8pm.
Operators affected include Thameslink, Lumo, LNER and Grand Central Rail.
Meanwhile an Overground service is partially suspended following a huge fire at a waste facility in Deptford earlier this week.
The Windrush line is not running between Surrey Quays and New Cross, according to TfL.
If you've been affected by what happened on the network today, there is always someone to talk to. You can contact the Samaritans on 116 123 from any phone for a confidential chat.
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Train companies respond to disruption
Major disruption to Stansted Airport trains
A fault with the signalling system in the Stansted Airport area means trains running to and from from the station are facing major disruption, National Rail has said.
It said trains may be delayed by up to 40 minutes, revised or cancelled.
Major disruption is expected until 8.15pm.
The following routes are affected:
CrossCountry between Stansted Airport and Cambridge / Birmingham New Street
Greater Anglia between Stratford (London) and Bishops Stortford, and London Liverpool Street and Stansted Airport / Cambridge / Cambridge North / Ely
Stansted Express between London Liverpool Street and Stansted Airport.
Severe delays on the Mildmay line
There are severe delays between Willesden Junction and Richmond and minor delays on the rest of the line due to train cancellations.
Minor delays on the Elizabeth line
There are minor delays on the Elizabeth line between Paddington and Reading due to a signal failure in the Slough area.
Minor delays on the Hammersmith and City line
There are minor delays on the Hammersmith and City line due to train cancellations.
Lines reopen between Finsbury Park and Welwyn Garden City
Lines have reopened between Finsbury Park and Welwyn Garden City
Services will be subject to residual disruption, and passengers have been advised to allow at least 45 minutes extra to complete their journey.
As a result of alterations and cancellations, passengers will likely need to travel on a different train to normal, or change trains at an intermediate station to complete your journey.
You are strongly advised to check journey planners before you travel. If you're travelling now, you should check station screens and listen to announcements for the latest information.
Minor delays on the Central line
Minor delays are affecting the Central line due to a points failure at White City.
Lines reopen between London King's Cross and Stevenage
The emergency services have now completed their work following an earlier incident where a person was hit by a train.
All lines between London King’s Cross and Stevenage have reopened.
However, as services recover, trains may still be delayed by up to 60 minutes, revised or cancelled.
Major disruption is expected until 5pm.
What services are disrupted by the Farnborough incident?
Long distance and mainline South Western Railway services between Exeter St Davids and London Waterloo are currently disrupted.
Some services will be delayed while others may be cancelled or revised.
Passengers have been asked to use the following routes to avoid disruption:
Great Western Railway services between:
• Reading and London Paddington
• Basingstoke and Reading
• Exeter and London Paddington
• Weymouth and Westbury
• Westbury and Reading
• CrossCountry services between Bournemouth and Reading
South Western Railway are arranging various replacement buses between Woking and Weymouth.
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