One person has died and three others rushed to hospital after an “inferno” at a block of flats in Bedfordshire.
The victim, who has not been named, was found as emergency services searched the three-storey building on Monday - with the fire thought to have been caused by a gas explosion.
Fire chiefs fear the blast may have been the result of someone using a camping stove due to soaring energy costs.
One patient has a serious leg injury and two - including a firefighter - suffered smoke inhalation and were all taken to hospital, East of England Ambulance Service has confirmed.
Bedfordshire Police Chief Superintendent John Murphy said more bodies may be found in the coming days as emergency services enter the flats.
He said: "Very sadly we know that at least one person has passed away in the explosion today.
"There is a possibility that there will be more fatalities discovered in the coming days as we continue to search through the scene and a number of people, as my colleague from the fire services has identified, were injured as well today.
Residents in 100 homes were evacuated with 36 properties destroyed.
Chris Bigland, deputy chief fire officer for Bedfordshire, said: "Gas wasn't linked to the building. There may have been gas bottles used for heating or cooking.
"It could have been a camping stove with the fuel crisis and rest of it. We can't rule it out - we just don't know."
Mr Bigland confirmed that two people were in hospital due to the fire. He said a firefighter was also treated for smoke inhalation as a precaution.
He declined to provide further details on the victims, who are said to be male residents aged in their 20s and 50s.
However he confirmed that people had left the building by 'unconventional methods' and that firefighters had helped people to evacuate.
He said: "When crews arrived people were looking to hang out of the building."
Footage shared on social media shows flames erupting from the building as hero firefighters try to battle the blaze after neighbouring properties were evacuated.
Local residents described feeling the ground shake and seeing a person jumping from a second-floor window to escape the burning building.
"I heard the explosion from my house round the corner," said one resident, who wished to remain anonymous.
"I walked to town and saw the flames and also witnessed someone jump from the second-floor window whilst flames were blaring out."
Adrian Marz, who lives on the top floor of the neighbouring building, told how he and his partner rushed to "start knocking on people's doors" and help evacuate the area.
"When I was outside the building I saw the walls being torn apart... and all of the windows out, and smoke and flames pretty much instantly", he told the BBC.
"I saw a couple of people jump out of the building and started helping them out... bringing them away from the fire, away from the danger, but it was a very, very serious and very big explosion.
"We saw people jumping out from the flat that was directly affected. I think that was the flat that blew up, and that was where the gentleman jumped out and hurt his hip really badly. We pulled him away."
Adam Fisher, a 37-year-old sales worker whose office is nearby, said he heard a "huge explosion" before witnessing "an inferno" at the site and people screaming.
He said: "A huge explosion heard - everyone went to our work car park to see what was happening.
"Our building is adjacent to the apartment complex - immediately an inferno (was) visible, huge smoke cloud billowing, people screaming and people frantically calling for emergency services."
Another concerned member of the public reported hearing an explosion moments before spotting smoke coming from the area.
She said: "Was working in a shop nearby. Explosion shook the whole shop and the ones near us.
"Next thing we knew we could see smoke coming from Redwood Grove.
"Scary stuff."
