A broken down train at Plumstead is causing delays between London Bridge and Dartford.
Southeastern reported problems just before 12pm and on Twitter said alternative transport is available.
The operator tweeted: "London Buses are still accepting tickets between Dartford and Lewisham because of a train fault between Plumstead and AbbeyWood."
According to Southeastern the faulty train has been moved (midday) but "possible disruption" is expected until around 2pm.
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