She admitted that it we be an "absolute miracle" if there was still anyone alive in the tower and that it would take "weeks" to complete a proper search with the building still unstable.
"We should call it what it is, it's corporate manslaughter.
We owe that to the families, to the people who have lost loved ones, friends, and the homes in which they lived".
At least 17 people were killed in the early morning inferno Wednesday that swept through the 24-story Grenfell Tower, trapping people inside their apartments before firefighters could arrive.
Commissioner Cotton revealed "a good half" of the building had yet to be searched in detail. Her staff will remain on scene for "days to come" and that the search of the tower would be a "slow and painstaking process".
Smoke was still wafting out of the shell of the Grenfell Tower on Thursday, and a Reuters cameraman saw a big piece of building cladding fall from the building.
The project included installing insulated exterior cladding, double-glazed windows and a communal heating system.
"If the fire alarm was working, most people would be safe", he said.
A CHILD praised fearless firefighter, police and ambulance heroes for saving lives in the Grenfell Tower inferno in a touching thank you card.
A blog post from Grenfell Action Group in November said "only a catastrophic event" would expose the concerns residents had.
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Accusations of obstruction arose last month when Mr Trump sacked Federal Bureau of Investigation director James Comey . Officials announced that President Donald Trump is under investigation for possible obstruction of justice .
May ordered a full public inquiry.to ensure that "this awful tragedy is properly investigated". The cladding material added in that renovation is now being blamed by experts as one of the reasons the fire spread so quickly.
Steve Apter, Director of Safety and Assurance at London Fire Brigade, said emergency crews had "to get through particularly arduous conditions up to the top floor".
An investigation into the cause of the blaze, the worst in the British capital in a generation, was underway.
Residents of the huge Grenfell public housing complex, which had 120 apartments that housed as many as 600 people, said their warnings about possible fire risks had been ignored for years.
Ian Burgess, a professor of structural engineering at the University of Sheffield, told CNN that while fires do spread vertically up buildings, it's "generally quite a slow process".
He said: "The building itself is in a very hazardous state".
May met with hospitalized survivors Friday after coming under criticism for failing to meet with angry residents of the building earlier in the week. Planning application documents filed with the council detail plans to provide the building with a rainproof cladding, using the Reynobond brand of panels.
Prime Minister Theresa May has vowed to hold an official inquiry as to what happened. She said she had attended the scene to get a briefing from the emergency services and had been "overwhelmed by their professionalism and their bravery".
Mr Corbyn told MPs: 'Properties must be found, requisitioned if necessary, in order to make sure that residents do get rehoused locally'.
Whole families are said to be among the missing, including Bassem Choukeir, his wife Nadia, her mother Sariyya and the couple's three daughters Mirna, Fatmeh and Zaynab.
Piles of prams, luggage, food supplies, toys and furniture could be seen stacked on the streets as mourners and well-wishers wrote messages of solidarity and hope on posters near the ruined tower.