Track defect causes train delays and cancellations
A track defect and a shortage of signalling staff has led to major disruption to trains between London Paddington and both Heathrow Airport and Reading.
National Rail's passenger information website warned Elizabeth line, Great Western Railway and Heathrow Express services were all being affected.
Elizabeth line services to Heathrow Terminal 5 have been suspended and trains between Paddington and Reading are subject to cancellation or delay, with disruption expected until the end of Tuesday.
Trains were initially unable to run between Heathrow Airport and London Paddington at all but the route was later reopened for Heathrow Express, albeit with a reduced service.
A reduced Elizabeth line service is also running to Heathrow Terminal 4.
Network Rail said engineers discovered the track defect on the high-speed line towards Paddington in the Acton area of west London, adding it had limited the speed which trains could travel, causing delays.
It continued by saying the track would be monitored throughout the day "to ensure trains continue to travel safely", until it can be replaced, and apologised to passengers for the disruption.
A member of signalling staff being unwell caused further delays, but a replacement staff member was found, Network Rail said.
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