Residents are reported to have been evacuated as 20 fire engines and around 125 firefighters were called to a "serious" fire in Walthamstow, east London.
The blaze near Vallentin Road and Shernhall Street has affected one house, multiple gardens and sheds as well as a railway embankment, London Fire Brigade (LFB) said.
People in the area were advised to keep their windows and doors closed due to a "significant amount of smoke", but the advice has since been lifted.
Motorists were also advised to avoid the area, and the Weaver Overground railway line was partially closed.
More than 100 calls were made to the fire service from around 6.30pm on Sunday.
Local MP Stella Creasy said there had been "an electrical fire on the train lines", but LFB said the cause of the blaze is unknown.
"We have got a major incident in Wood Street," she said. "There is a serious fire with a lot of roads and people being evacuated."
LFB said two rest centres have been set up for residents affected by the fire, which in a later update Ms Creasy said were being closed down as most residents were allowed to return home.
She said there were no known injuries, while most properties in the area had not been damaged, although there has been damage to sheds and gardens.
(c) Sky News 2026: Residents evacuated as 125 firefighters called to 'serious' UK fire
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