"Huge explosions" have been reported after 11 buses caught fire at a depot in southeast London.
Seven buses were "complete destroyed" by the blaze on Farnborough Hill in Orpington, London Fire Brigade (LFB) said, while four more were badly damaged.
A further 30 vehicles were moved to a safe area as crews worked to stop the flames spreading.
Amy Spencer tweeted that she had been "woken up by 10 huge explosions and what looks like a big fire".
Cat Fitzmaurice said she had been woken "by explosions at 4am".
Eight fire engines and 60 firefighters were sent to tackle the flames after LFB was called at 3.36am.
It took around 40 calls about the "very visible" incident.
The brigade later said that "while the fire is now under control, crews will remain in the area for some time damping down the affected vehicles".
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Travel in the area may be difficult because of the "number of appliances in attendance", LFB said.
The cause of the fire is not known.