Fire broke out in the 24-storey Grenfell Tower, a social housing block in Kensington, west London, in the early hours of Wednesday, trapping residents inside as it tore through the building with terrifying speed.
"I believe there are 79 people that are either dead, or missing, and sadly I have to presume are dead," Metropolitan Police Commander Stuart Cundy told reporters.
He said that five of the dead had been formally identified and it would be a slow and painstaking task to identify the others. Because of the intensity of the blaze some may never be identified.
A minute's silence was held across Britain at 1000 GMT to honour the victims of the fire - a painfully familiar ritual after the country has been hit by three deadly attacks by Islamist extremists in London and Manchester since March.
At an improvised memorial wall covered in messages of grief and solidarity close to Grenfell Tower, firefighters and members of the local community stood together, some crying, as they observed the minute's silence.
One firefighter, in his black protective suit with FIRE emblazoned in yellow on the back, embraced a distraught woman who had photos of a missing person printed on her top.
A red t-shirt with the London Fire Brigade's logo had been placed by the memorial wall, with the name of a nearby fire station and the words "We tried, we're sorry" scrawled on it.
Briefing reporters at police headquarters, Cundy became visibly upset as he described conditions in the charred tower, where a search and recovery operation is expected to last weeks.
"I was in there myself and went all the way to the top floor and it is incredibly hard," he said, before pausing as tears welled up in his eyes.
"It is incredibly hard to describe the devastation in some parts of the building," he continued, his voice breaking.
"NOT GOOD ENOUGH"
The fire has come at a particularly difficult time for Prime Minister Theresa May, who was weakened by the loss of her parliamentary majority in a June 8 election and faces arduous talks on Britain's exit from the European Union.
Emergency services have been widely praised for their response to the fire, but the local community has accused the government of a slow and inadequate reaction. May has come under personal attack for failing to meet residents during her first visit to the site.
At a daily briefing with reporters, May's spokeswoman said that on a second visit to the area, during which the prime minister was booed and heckled, May had listened carefully to the experiences of those on the ground.
"That's why she totally accepted that it (the government response) hadn't been good enough. She understood that immediate action needed to be taken to speed things up, and that's what she's done," the spokeswoman said.
May's spokeswoman said later on Monday that staff from five government departments are now working on the ground, including officials from the Foreign Office. A pledge that survivors would be re-housed locally would be met within three weeks, she said, adding that reports of people being offered homes hundreds of miles away were false.
However, May did not support a proposal put forward by Jeremy Corbyn, leader of the opposition Labour Party, to seize unoccupied properties to re-house survivors of the fire, the spokeswoman said.
"Occupy it, compulsory purchase it, requisition it - there's a lot of things you can do," Corbyn said on Sunday during an interview on ITV.
"WHY THIS HAPPENED"
Grenfell Tower is located in a pocket of social deprivation within the borough of Kensington and Chelsea, one of Britain's wealthiest areas. The fire has led to national soul-searching about inequalities and neglect of the poor.
Cundy said a criminal investigation into the tower blaze would be exhaustive and that 250 investigators were looking at all criminal offences that may have been committed.
"Whilst it will look at the how, perhaps more importantly, it will also look at why this happened," Cundy said.
The investigation will include areas such as the construction, renovation and maintenance of the building and fire safety procedures, he said.
Cundy said that five people reported as missing in the fire had now been found and were safe and well.
He said the death toll of 79 could still change if anyone reported as missing was found alive, or if anyone was found in the ruined tower who had not been reported as missing.
"Whilst I've said I think there may be changes, I don't think those changes will be as significant as the changes we've seen over the last few days," he said.
The death toll was first given as 12 before being revised up to 17, then 30, then 58.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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