A fire broke out in a property in south-west London after a man burnt timber on an open fire in his living room to heat his home, London Fire Brigade has said.
Investigators said the cause of the blaze was identified as an open fire being used instead of gas central heating, prompting the fire service to issue an urgent safety warning.
It is understood to have also been caused by combustible items placed too close to an open fire.
London Fire Brigade said there have been more than 100 fires involving open fires, log burners and heaters in the last few months alone.
The brigade now fears the rise in energy bills could result in a surge of fires as people resort to alternative means to heat their homes throughout the colder spells of the year.
Fire crews were called to the scene in Kingston Road, New Malden after flames spread through the property which suffered “significant damage”.
London Ambulance Service said it treated three people at the scene, with one man being taken to hospital as a priority. No further details on their injuries have been given.
A witness said they saw the man trying to put out the blaze with a fire extinguisher when it started while a policeman, who happened to be passing by, began knocking on the windows of the adjacent property to make sure the residents got out.
One neighbour, who declined to give her name, said: "You could not see [anything] as the smoke was so thick. It was just unbelievable.
"I shut all my windows and whenever I opened the door to let someone in some smoke came into the hallway."
She added that people taking their children to school were seen getting off buses and travelling by foot on Kingston Road due to the blanket of smoke.
A next-door neighbour has temporarily moved out of her house due to minor smoke and water damage to their property, the neighbour said.
Deputy assistant commissioner for fire safety Charlie Pugsley said: "We know this is a difficult time and people are thinking about ways to reduce their energy bills, but we’re really concerned that they may be putting lives at risk by doing so.
"If you do have a log burner or an open fire, follow our advice carefully. Almost 30% of fires involving log burners, heaters and traditional open fires are caused by items being placed too close to a heat source. Always use a fire guard and keep anything that could catch alight well away, such as logs and kindling which could be ignited by radiating heat.
"It’s also important to make sure you have carbon monoxide alarms in your home. You can’t taste, see or smell carbon monoxide fumes, but it can kill in minutes.
"Please don’t take the risk by using treated wood on fires. Not only can they produce toxic fumes, but they are also more likely to spit embers when burnt, which could set alight to nearby objects."
Last year, the Government brought in new laws surrounding fire safety with an aim to make homes and buildings safer following the fatal Grenfell Tower fire in 2017.
A Government spokesperson said: "We recognise the pressures people are facing with the cost of living, which is why we have set out a £22 billion package of support, including rebates and energy bill reductions.
"Anyone struggling to pay their energy bills should contact their supplier as soon as possible to work out an affordable payment plan, which suppliers are legally obliged to agree to."
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