Four fire engines and 21 firefighters and officers were sent to tackle a fire in a block of flats on Pocock Street late on Sunday night.
One man left the flat before the arrival of the brigade and was uninjured.
Part of a flat on the second floor was damaged by fire.
Firefighters from Dowgate, Lambeth and Old Kent Road fire stations attended the incident.
The cause of the fire is under investigation.
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