London fire: Pictures reveal scale and horror of Grenfell Tower devastation
Devastating images of the charred interior of London's Grenfell Tower verge on "indescribable", and police say the death toll is expected to rise.
Photos released by London's Metropolitan Police show the destruction caused by last week's deadly inferno.
One photo shows a burnt-out elevator on an undisclosed floor of the public housing project that was ravaged in Wednesday's inferno, while another shows an apartment that was reduced to rubble and white ash.
The tragedy destroyed much of the west London apartment block on June 14 and claimed the lives of at least 58 people.
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Police Commander Stuart Cundy told the Daily Mail the conditions inside the fire-damage tower verged on "indescribable".
"It is really important that we are clear about the scale of the challenge facing us as our teams search Grenfell Tower to recover those people still inside and return them to their loved ones."
Cundy said a full forensic and systematic search was being carried out, but people must prepare for the worst.
"Whilst our teams have been from the bottom to the top of the tower, we must now carry out a full forensic and systematic search.
"The conditions due to the fire damage verge on indescribable, which is why this will be such a lengthy operation taking weeks to complete.
"We must also prepare people for the terrible reality that some people may not be identified due to the intensity of the fire."
Police said on Friday they were looking at possible "criminal offences" behind the fatal fire.
Their investigation into the fire would "establish the facts and provide answers" as to the cause of the fire, Cundy said.
Police would "look into what criminal offences may have been committed", he said, without giving details of who police suspect may be to blame for the fire, or what kind of offences they are investigating.
Sir Keir Starmer, the Shadow Brexit Minister and former Director of Public Prosecutions (DPP) has said prosecutors were already part of the current investigation, The Telegraph reported.
"I spoke to the DPP yesterday and there are prosecutors already in advising the police," said Starmer.
"Normally an inquest will only take place at the end of the criminal investigation, so the idea of an inquiry is important because that can, in some circumstances, happen much more quickly and I think speed is of the essence here.
"There are wider regulatory offences but I think manslaughter is the most serious and that's the one that needs to be looked at first.
"So a public inquiry allows things to happen more quickly and allows a broader range of questions and inquests come usually at the end of the exercise."
Police said on Sunday (local time) the number of people assumed to have died in the London tower block fire was likely to rise from 58.
If the number is confirmed, it would make the Grenfell Tower blaze the deadliest in London since World War Two. The toll had previously been put at 30.
While the blaze has prompted an outpouring of generosity, with many people donating provisions and clothes, it has also unleashed rage at the authorities as the charred tower was cast as a deadly symbol of a deeply divided society.