Detectives will go through the Grenfell Inquiry report line by line as they have “one chance” to get their investigation right, a senior officer has said.

Those affected by the disaster face a wait of another year to 18 months from the report’s publication before they find out whether any criminal charges will be brought over the tragedy.

Police and prosecutors said in May that investigators will need until the end of 2025 to complete their inquiry, with final decisions on potential criminal charges by the end of 2026.

A man in a room with files of evidence
Detective Superintendent Garry Moncrieff at the warehouse where thousands of exhibits are being stored (Lucy North/PA)

Metropolitan Police Deputy Assistant Commissioner Stuart Cundy said on Wednesday: “Our police investigation is independent of the public inquiry.

“It operates under a different legal framework and so we cannot simply use the report’s findings as evidence to bring charges.

“To secure justice for those who died and all those affected by the fire we must examine the report, line by line, alongside the evidence from the criminal investigation.

“As I said previously, this will take us at least 12 to 18 months.

“This will lead to the strongest possible evidence being presented to the Crown Prosecution Service so they can make charging decisions.

“I can’t pretend to imagine the impact of such a long police investigation on the bereaved and survivors, but we have one chance to get our investigation right.

“We will be thorough and diligent in our investigation while moving as swiftly as possible. We owe that to those who died and all those affected by the tragedy.”

In May, the Met said its mammoth inquiry into the fire, which killed 72 people in 2017, had generated 27,000 lines of inquiry and more than 12,000 witness statements.

A total of 19 companies and organisations were under investigation for potential criminal offences, along with 58 individuals, and more than 300 hours of interviews had taken place.

Grenfell memorial
A memorial for the 72 people killed in the Grenfell Tower fire (Lucy North/PA)

Potential offences under consideration included corporate manslaughter, gross negligence manslaughter, perverting the course of justice, misconduct in public office, health and safety offences, fraud, and offences under the fire safety and building regulations.

At that stage eight out of 20 files had been sent to the CPS for early investigative advice, with a typical case file more than 500 pages long with 17,000 pages of evidence.

Up to the end of March this year, the Met had spent £107.3 million on the inquiry, and in May there were 180 investigators working on the case.

Officers had retrieved more than 152 million files, gathered 75,000 photos and 27,000 exhibits.

Forensic teams spent 415 days examining the tower itself after the deadly blaze and painstakingly gathering evidence.

Exhibits are being stored in an enormous warehouse that is big enough to store 25 double-decker buses.

It includes the charred remnants of cladding panels that would have had molten plastic dripping down them while the building was on fire.