A derailed freight train is causing disruption to high-speed passenger services to and from London St Pancras International.
Network Rail said the “low-speed” derailment happened at the Hoo Junction depot between Gravesend and Strood in Kent in the early hours of Thursday.
One of the train’s wheels came off the rails, leading to several wagons blocking southbound lines.
This is causing delays and cancellations to passenger services operated by Southeastern.
High-speed services from London St Pancras International towards Strood are being diverted after Ebbsfleet International.
Southeastern warned that trains heading towards the capital “may be delayed or amended at short notice”.
The derailment also means that all trains from Gravesend towards Rochester are cancelled.
Network Rail said it will use a “rescue locomotive” to remove the wagons blocking passenger trains.
It posted a message on Twitter apologising to passengers, adding: “These recoveries can prove tricky sometimes so please continue to check before you travel for the latest information and alternative options.”
Disruption is expected to continue until noon.
Southeastern travellers were already facing a reduced service as an emergency timetable was introduced on Monday in response to coronavirus pandemic-related staff shortages.
Operators across Britain have taken the same measure in an attempt to reduce the number of short-notice cancellations.