Experts believe the building's new exterior cladding, which contained insulation, helped spread the flames quickly up the outside of the public housing tower early Wednesday. Some said they had never seen a building fire advance so quickly.
Hands and Treasury chief Philip Hammond said in separate TV appearances that the cladding used on Grenfell seems to be prohibited by British regulations. Hands cautioned that officials don't yet have exact details about the renovation that ended just last year.
"My understanding is that the cladding that was reported wasn't in accordance with U.K. building regulations," Hands told Sky News. "We need to find out precisely what cladding was used and how it was attached."
Aluminum cladding with insulation sandwiched between two panels has been blamed for helping to spread flames in major fires in many parts of the world, including blazes in the Middle East, Europe, Asia and the United States.
Labour Party lawmaker David Lammy demanded that the government and police immediately seize all documents relating to Grenfell's renovation to prevent the destruction of evidence that could show criminal wrongdoing.
"The prime minister needs to act immediately to ensure that all evidence is protected so that everyone culpable for what happened at Grenfell Tower is held to account and feels the full force of the law," Lammy said, suggesting that contractors might be destroying evidence before it is sought by police.
He said all records — including emails, minutes of meetings, correspondence with contractors, safety assessments, specifications and reports — must be kept intact.
"When the truth comes out about this tragedy, we may find that there is blood on the hands of a number of organizations," Lammy said.
He complained bitterly that a friend — the young artist Khadija Saye — was still alive three hours after the fire started but was unable to get out of her apartment to safety.
Police Commander Stuart Cundy says police will seek criminal prosecutions if the evidence warrants. He has not provided details about the inquiry.
London Mayor Sadiq Khan said Sunday after attending a church service several blocks from the tower that the fatal blaze was entirely preventable.
He said displaced residents are "angry not simply at the poor response in the days afterwards from the council and the government, but the years of neglect from the council and successive governments."
They feel they have been ignored because they are poor, he said.
British officials have announced a nationwide minute of silence to honor the victims on Monday morning.
Frustration has been mounting in recent days as information about those still missing in the blaze has been scanty and efforts to find temporary housing for the hundreds of now-homeless tower residents have faltered.