Four people - including the attacker have now died, and 40 are injured after yesterday's terror attack in London.
Major Disruption On Southeastern Trains
Southeastern tweeted shortly after 6am to say the train had derailed in the Lewisham area, adding: "All services through the area will be disrupted, with some services suspended."
Kent commuters are suffering major disruption on Southeastern services after a freight train derailed in south east London.
It has led to some services being suspended, cancelled and diverted.
The firm said tickets would be accepted on bus routes, Underground services and on other rail and tram services in the area.
Southeastern added: "Disruption is expected to last all day. Please make sure you check before travelling.''
Network Rail said the derailment happened shortly before 6am and that it had a team of engineers at the site by 6.15am.
There were no passengers aboard and no-one was injured in the incident.
A Network Rail spokesman said: "Owing to a freight train derailment between Lewisham and Hither Green services are severely disrupted into and out of Charing Cross and Cannon Street.
"Passengers are advised to check their journey before they travel.''
Southeastern passengers vented their frustration on Twitter.
One user, Nicky W, said: "Another day another #southeastern disaster. Freight train derailed at Lewisham. Don't think I will rush...''
Colin Twigg wrote: "No trains to Hastings from London Bridge at all?! Because a freight train derailment at Lewisham that's not even on that line?!'', while Emilie Murphy added: "Derailed freight train at Lewisham means Uber to Kings Cross. Think I'll still miss my train - @virgineastcoast will you honour tickets?''
The derailment means trains cannot run between Dartford and Lewisham via Sidcup, with a shuttle service being arranged between Sidcup and Dartford.
Trains are not running from Hastings towards London, while those from Ramsgate that normally run to Charing Cross are being diverted to London Victoria.
Services starting and terminating at both Tunbridge Wells and Sevenoaks are also suspended.
Site in Kent earmarked for development
The inquest into the deaths of three people, found at cliffs in Dover, is due to start.
An Ashford woman who stole around £100,000 from the company she worked for has been sent to prison.
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