A battery which caused a house fire that killed a mother and three children was from an e-scooter, the fire service said.
Merseyside Fire and Rescue Service (MFRS) said the lithium-ion battery was not inside the scooter at the time and is believed to have been on charge when the fatal fire started.
The blaze broke out at the home of Elisha Brabin, 36, in Bootle, Merseyside, last Tuesday, killing her children Leo, 16, Ellis, 8, and seven-year-old Prudence.
On Monday, the MFRS said an electrical fault caused the battery to go into thermal runaway, which occurs when the battery generates more heat than it can safely release, causing its temperature to rise dangerously.
Ms Brabin and her children were found in an upstairs bedroom by firefighters who were called to the home at about 3.45am.
Another person was taken to hospital suffering from burns.
Kev Johnson, head of prevention at MFRS, said: "I would like to commend the efforts of our fire control staff and our fire crews, also working with NWAS colleagues, who made every effort to provide a different outcome, but sadly this was not the case due to the speed and intensity of the fire.
"This tragedy highlights the very real risks posed by lithium-ion batteries, which we confirmed as the source of the fire."
The MFRS said there had been 150 fires linked to lithium-ion batteries in Merseyside between April 2023 and August 2026, and five fatalities linked to the batteries.
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Mr Johnson added: "We're urging people to follow the manufacturer's instructions, only using batteries and chargers which have been supplied with the vehicle or approved by the manufacturer, as anything else can pose a huge fire risk.
"It's also important to know and recognise the signs that your lithium-ion battery may be failing - if it is swelling, making unusual sounds, has a strong smell, is failing to charge, or is smoking, please stop using immediately."
Following their deaths, the family of Ms Brabin said she was a "devoted and loving mother who lived for her children".
They said: "The tragic loss of Elisha and our three precious children has left us heartbroken. They have all been taken from us far too soon.
"The loss we are experiencing is unimaginable, and the impact on our family will be felt forever."
(c) Sky News 2026: E-scooter battery ignited house fire that killed mother and her three children
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