Train tracks are shut near to the station while the Jubilee line is also part suspended.
Image source, Network Rail Kent & SussexMore than 70 firefighters are tackling two separate blazes near London Bridge.
A major fire in the railway arches on Union Street, Southwark, was reported just after 09:20 BST and 10 crews are working to bring it under control.
Another three fire crews are at London Bridge station, where a smaller fire has also broken out, causing heavy smoke.
Network Rail said four rail lines have been closed, while the Jubilee line on the Tube is also part suspended.
Please avoid the area whilst we work to bring the fire under control in #Southwark. There is a lot of smoke – so keep windows and doors closed https://t.co/5xIpC4mpKN https://t.co/t7x6o86zCV
— London Fire Brigade (@LondonFire)
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