At least 17 people have died in the Grenfell Tower fire, although the death toll is still expected to rise, emergency services have said.
Specialist urban search and rescue teams are being brought in to make the 24-storey tower block safe in north Kensington to allow firefighters and the police to carry out investigations, following the devastating blaze that started in the early hours of Wednesday.
Search dogs will also be used to help locate the missing in the wreckage.
Commander Stuart Cundy, of the Metropolitan Police, said: "Sadly I can confirm that the number of people who have died is now 17.
"We do believe that that number will sadly increase."
Detective Chief Inspector Matt Bonner has been appointed to lead the investigation, he added.
London Fire Commissioner Dany Cotton said: "This will be a detailed fingertip search.
"Obviously this will be a very slow and painstaking process."
Speaking from the scene, as family and friends of Grenfell residents continued the desperate search for information about the whereabouts of their loved ones, Mr Cundy said: "There are still a number of people who are receiving treatment in hospital.
"There are 37 people receiving treatment, of which 17 are still in critical care.
"Like we explained yesterday, our absolute priority for all of us is about identifying and locating those people that are still missing.
"It would be wrong for me to get into numbers that I do not believe are accurate."
The flats were home to between 400 and 600 people, community leaders said.
More than £1 million has been raised to help those affected by the fire, while volunteers and charities helped feed and shelter people who could not return to their homes overnight.
A wall of condolence was put up near the scene, with photographs showing dozens of messages left for loved ones.
Prime Minister Theresa May has promised a "proper investigation" after the building went up in flames amid growing concerns about how the blaze could have spread so rapidly.
Prime Minister Theresa May visited the scene on Thursday morning, speaking with firefighters and police officers inside the vast cordoned-off area around the fire site.
She was whisked away by car shortly after 10am without speaking to reporters.