More than 400 train services run by Southeastern have been cancelled today as a result of a fire at a workshop in railway arches in Bermondsey, south east London.
The disruption comes just a month after hundreds of trains services in south London and Kent had to be cancelled because of a lineside fire, that time in Deptford, near to New Cross Junction.
London Fire Brigade, which has more than 40 firefighters and eight appliances at the scene, have thrown a 200 metre hazard zone around the area of the fire in case gas bottles explode.
This has led to the closure of all railway lines between New Cross and London Bridge, one of the busiest stations in London.
Southeastern said the closure of the lines was likely to cause major disruption to mainline and suburban services in and out of London Bridge, London Cannon Street, London Charing Cross and London Waterloo East.
The train company has brought in an emergency timetable and some services are being diverted to London Victoria and Blackfriars stations.
Southern services have also been affected by the fire and the company is advising passengers to use London Victoria station. First Capital Connect services from and to Brighton are being diverted via Herne Hill.
Southeastern said that ticket holders would be allowed to use all reasonable bus, Tube and Docklands Light Railway routes to help complete their journeys.
But delays and cancellations are inevitable, possibly for the next 24 hours, and so passengers are advised to check before making journeys in and out of London.
A Southeastern spokeswoman said every effort was being made to ensure that passengers got home tonight. "The fire brigade will tell us when we can resume services," she said.
Updated information will be made available on Southeastern's website, www.southeasternrailway.co.uk, through National Rail Enquiries (08457 48 49 50), Teletext and via local radio and television stations.