An inferno which engulfed a tower block, killing at least 12 in what could become one of the biggest fire tragedies in British history, was a "disaster waiting to happen", experts have said.
Fears were raised that green energy concerns were prioritised ahead of safety as it emerged that cladding used to make the building more sustainable could have accelerated the fire.
On Wednesday night, police confirmed 12 people had died following the blaze at Grenfell House in Kensington, west London, but they expected the death toll to rise.
Hundreds of the roughly 500 residents in the block were unaccounted for. Some estimated that the death toll could rise above 100.
A total of 74 people were being treated in hospitals, with 20 of them in a critical condition after the fire, thought to have been sparked by a faulty refrigerator, started just after 1am on Wednesday and quickly spreading up the building.
There were fears children were among the dead as survivors told how they saw babies being thrown from windows in the hope that they could survive.
Residents knotted sheets together to make ropes in attempts to escape. Some tried to manufacture makeshift parachutes from bin bags and bedding and leap out of windows.
Many of those that survived only did so by ignoring official advice to stay in their rooms and close their front doors until the fire was over.
Mickey Paramasivan, 37, said: "There were explosions everywhere you looked, lots of bangs, blue gas coming out everywhere you looked.
"About 12 floors up I saw three children waving from a window and then there was just an explosion and they disappeared.
"They were three kids, they were banging on the windows, you could see their silhouettes and then bang, it just went up."
But as emergency services continued to search the 24-storey building for victims, there were claims that warnings about safety had been ignored.
Government ministers were warned about the fire risk of cladding as far back as 1999, the Daily Telegraph can reveal.
It was installed on the council-owned Grenfell block in 2015 as part of a £10 million refurbishment by a company which was later liquidated after a firm they were working with refused to pay out in a dispute over their work.
Tens of thousands of buildings in the UK have been fitted with cladding, it is estimated, leading to calls for an immediate review of safety.
Experts said that the cladding - which is used to insulate the building - had acted like a "chimney" for the flames by allowing the fire to spread upwards through the gaps between the cladding and the building walls.
Residents had warned that the tower block was a "catastrophe" waiting to happen but their complaints "fell on deaf ears", they said yesterday.
Reg Kerr-Bell, the former chairman of the Kensington and Chelsea Tenant Management Organisation (KCTMO) - the body which manages the building - said he stood down several years ago over safety concerns.
Just two days before the blaze, he had spoken to a former colleague about their fears.
Mr Kerr-Bell said: "This is a scandal. This is one of the biggest scandals in the country - and it could have been avoided...
"We felt there was a disaster waiting to happen and we were going to have a meeting with the MP so that we could put these concerns to them."
Mike Penning, a former fire minister, called for an urgent review into the use of the insulation material.
He said: "There has to be an urgent review into the use of cladding. We need to expedite this as far as possible - this cladding is used extensively in the UK and abroad."
Nick Hurd, the fire minister, said that checks are now being carried out on tower blocks that are going through a similar refurbishment process.
Matt Wrack, General Secretary of the Fire Brigades Union, said: "I have never seen a fire that has engulfed an entire building like this in a career of more than 30 years."
Theresa May's new chief of staff is facing questions over his role in a delayed fire safety review in the wake of the Grenfell Tower blaze.
Gavin Barwell, a former housing minister, has been accused of "sitting on" a review into building regulations at tower blocks after a deadly fire in South London in 2009.
Dr Jim Glockling, Technical Director of the Fire Protection Association, said that they had been lobbying the Government to review the safety of combustible materials used on the outside of buildings since 2014.
All fire safety regulations are focused on containing a fire within a building, but this cannot happen if it is spreading along the outside.
"There has been an emerging body of evidence surrounding some of the materials being used and now we have an appalling demonstration of what can happen," he said.
Alongside the cosmetic appeal of cladding, it is used as an insulation to make buildings more sustainable to meet green energy requirements.
"It could be that this is the quest for sustainability trumping other concerns," Dr Glockling warned.
Matthew Needham-Laing, an architect who is head of construction at Katten Law UK, said that the first known cladding fire in the UK was in 1991 and there had been concerns over in the industry about its fire safety for a number of years.
He said: "This is not a shock, the problems with cladding have been known about and talked about for a number of years and hopefully this will at least make people listen."
He said that some estimates were that 30,000 buildings had been fitted with cladding, which is a cheap way of making a building more sustainable without rebuilding it.
Senior Conservatives last night called for an urgent review.
It comes amid allegations of a litany of failings by Kensington and Chelsea council, who own the flats, and the Kensington and Chelsea Tenant Management Organisation (KCTMO) who are paid £11 million to manage property for them.
Residents have been complaining for the past four years about fires safety in the flats, warning that there would be a "catastrophe" and demanding that action was taken and the management by the company was reviewed.
KCTMO was deseribed by residents groups as a "mini-mafia" as they lambasted the management of art school graduate Robert Black.
Further questions were raised yesterday Rydon Construction, the company contracted to carry out £10million refurbishment which was completed in March last year, appeared to change their statement about the tragedy.
Rydon released a statement saying it met all "fire regulation and health and safety standards" during the refurbishment in 2016.
However a later statement omitted this line ans simply said the company had "met all required building regulations".
The company paid £3million to install the cladding, Harley Curtain Wall Ltd, has since gone bust after one of their customers refused to pay them almost £500,000 for disputed work.
The director of the company, Ray Bailey, who has since started a new firm Harley Facades Limited, said that they had used a common Aluminium Composite Material (ACM) panels which are a commonly used product in the refurbishment industry.
The London Fire Brigade warned ministers that building regulations were not taking into account the vertical fire issues that cladding could cause in 1999, warning that because of cladding regulations were "inadequate".
Glyn Evans from the Fire Brigades Union told a Select Committee on Environment, Transport and Regional Affairs that after the Great Fire of London only horizontal fires were considered and "we do not really recognise the problem of vertical envelopment. If you get multistorey buildings you will get fire spread up the outside if the cladding will permit it."
The Health and Safety Executive, the police and the fire service are now expected to launch a large-scale investigation into the safety of the building and whether regulations were complied with.