Flat doors in Grenfell Tower could only hold back a blaze for half the time they were supposed to, investigators have found.
Experts acting on behalf of the Metropolitan Police tested an undamaged front door from the west London block and found that it could withstand a blaze for 15 minutes - not the 30 for which it was designed.
Seventy-one people died when a fire ravaged the residential building on June 14 last year.
A statement by Housing, Communities and Local Government Minister Sajid Javid acknowledged in a statement to Parliament on Thursday morning (March 15) that the news “will be troubling for many people not least all those affected by the Grenfell tragedy”, but that the risk to public safety remained low.
A vast police investigation is continuing into the causes of the fire, Scotland Yard said, as it announced the new findings.
It said in a statement: "The Metropolitan Police Service is conducting a comprehensive investigation into what happened at Grenfell Tower in June last year.
"We have previously described that our forensic examination at the scene would be followed by a phase of offsite testing to be conducted by experts on our behalf.
"As part of this investigation, experts tested a flat front door taken from Grenfell Tower. The door tested was designed to resist fire for 30 minutes but during the test, it was only found to resist the fire for approximately 15 minutes, a much shorter period than expected.
"The forensic examination and testing phase is ongoing and we are not able to comment on the potential impact or otherwise that any test result may have on the overall criminal investigation.
"We have shared this information with the Ministry of Housing, Communities and Local Government as the appropriate government department, so that they are able to take any action required."
Mr Javid said the police considered the findings might have wider implication for public safety and alerted his department, which put together an expert panel made up of fire safety and building experts.
After consultation the panel advised the risk to public safety remained low, and that there was no change for fire safety advice that the public should follow.
He continued: “I nevertheless appreciate that this news will be troubling for many people not least of all those affected by the Grenfell tragedy.
“That's why based on expert advice we have begun the process of conducting further tests and will continue to consult with the expert panels to identify the implications of these further tests.”
He added: “My department and the Metropolitan Police will ensure that the bereaved and the survivors are kept informed of progress.”
And he warned: “I should stress that in carrying out these tests conclusions should not be drawn on the nature of the cause of the Grenfell tragedy. That is a matter for a separate police investigation and it must be allowed to run its course.”
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