The Corner Cafe at the junction of Lambeth Road and Hercules Road will remain closed "until further notice" after a fire in the basement on Thursday lunchtime.
Four fire engines and 21 firefighters and officers from Lambeth, Dowgate, Old Kent Road and Brixton fire stations were called to the scene.
The London Fire Brigade says that cause of the fire is not known at this stage but a notice posted outside the cafe blamed an "electrical fault" for the closure.
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