UK police may consider manslaughter charges after finding tower cladding failed safety tests in blaze that killed 79.

A fire that engulfed a London tower block, killing at least 79 people earlier this month started in a fridge-freezer, London police said, adding that cladding on the building failed all safety tests.

Police said that 79 people were dead, or missing and assumed dead, after the blaze rapidly spread through the 24-storey Grenfell Tower, which was built in 1974, on June 14.

Detective Superintendent Fiona McCormack said the Hotpoint model, FF175BP, was not subject to recall and that the manufacturer was doing further tests.

“We now have expert evidence that the fire was not started deliberately,” McCormack said before adding the police were considering manslaughter charges given the high number of deaths.

Police were also investigating companies involved in the building and refurbishment of the tower, and possible “health and safety and fire safety offences”, she said.

Exterior cladding and tiles recovered from the building have failed fire safety tests, said McCormack.

The cladding was installed on the council-owned building as part of a refurbishment completed last year.

Whirlpool Corp, the world’s largest maker of home appliances, owns the Hotpoint brand in the Europe and Asia Pacific regions. In the United States, the brand now belongs to Haier, following the Chinese group’s purchase of General Electric Co’s appliance business.

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“We are working with the authorities to obtain access to the appliance so that we can assist with the ongoing investigations,” Whirpool said in a statement.

“Words cannot express our sorrow at this terrible tragedy.”

The blaze prompted a wider review of social housing which has identified at least 600 towers in England with similar cladding.

McCormack repeated calls for anyone with information on who might have been in the tower to come forward.

“What we haven’t got is a picture of how many people might have been in there. That’s the number I’m really worried about,” she said.

Police fear the death toll may be higher because some residents may have been living in the tower illegally.

“Our forensic search may not be complete until the end of the year,” she added.

Prime Minister Theresa May stressed on Thursday that all victims, regardless of their immigration status, would be able to access whatever help they need.