Residents in Hackney have been urged to shut their windows and stay indoors after smoke billowed from a block of flats on Wednesday.
Locals described seeing thick clouds of black smoke coming from a building on Dalston Lane.
Fifteen fire engines and 100 firefighters from the London Fire Brigade attended the scene after reports of “significant amounts of smoke” coming from a four-storey block of flats.
Amy, who did not wish to share her surname, lives in Clapton just a few minutes from the fire and said the blaze was “devastating” for the community.
The youth worker, 34, said she saw thick smoke as she walked to the gym with her son and filmed the moment dark clouds billowed into the air.
She told the PA news agency: “I live five minutes from the fire and could smell the smoke in my home as I had windows open.
“My son and I went to use the gym at 6.30pm when I filmed the video. The smoke was growing thicker. Services had arrived.
“At 7.45pm, the police wouldn’t allow me to visit my friend who lives opposite the fire. Residents were being told to seek refuge in St John’s church.”
She added: “Living in Hackney has desensitised me to these types of incidents. As I spoke with my friend who lived opposite, I could see where the fire was.
“It’s devastating to the residents and community. Grateful to have seen support was more or less immediately available for residents and local people.”
Rosie Speirs, a Hackney resident, was standing on Clarence Road when she filmed the moment the building produced a large “dark fog”.
Ms Speirs told PA: “It was so horrible to see.
“Family bellowing about their homes, the smoke was visible from all areas of Hackney and filled the surrounding streets with a dark fog.
“I am praying everyone has a safe warm place to stay tonight.”
London Fire Brigade said one person is being treated for smoke inhalation but no other injuries were reported.
The fire service confirmed residents were taken to a nearby church while firefighters tackled the blaze and said it is working with the local authority to offer support to people.
In a statement, the London Fire Brigade said: “Fifteen fire engines and around 100 firefighters have been at the scene of a fire on Dalston Lane in Hackney.
“Part of a four-storey block of flats, including the roof, was alight. The fire has been producing significant amounts of smoke and people in the area were advised to keep windows and doors closed.
“The fire has now been brought under control by firefighters but crews will remain on scene throughout the evening fully extinguishing the fire and dampening down.”
It added an investigation is under way to understand the cause of the fire.
