The Hard Rock Cafe in Piccadilly was damaged by a fire that took the London Fire Brigade six hours to bring under control on Saturday.
Eight fire engines and about 40 firefighters were called to tackle the blaze at 5.10pm, which started in the extraction ducting.
Nearly a quarter of the ground floor restaurant was destroyed, and smoke was seen billowing from the roof of the building.
About 60 staff and customers were evacuated from the building on Old Park Lane, but there were no casualties reported.
Fire investigation officers believe the blaze was started accidentally.
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