LONDON — Around 600 high-rises are believed to be covered in similar cladding to the material suspected of worsening the deadly London apartment block fire, the British government said Thursday.

Residential towers around the U.K. are being examined after the inferno, which left 79 people dead or missing.

Three buildings have been found to be covered in the same combustible material used on the outside of Grenfell Tower, which rapidly burned up early on June 14 while dozens of residents were trapped inside.

"The relevant local authorities and local fire services have been informed, and, as I speak, they are taking all possible steps to ensure buildings are safe and to inform affected residents,” Prime Minister Theresa May told lawmakers in the House of Commons.

A spokesman for her office at 10 Downing Street said 600 tower blocks across England are covered in similar cladding, based on estimates provided by local governments. However, it isn’t yet clear how many are combustible.

The local government in the London borough of Camden said it was already planning to remove the cladding from its towers.

Cladding has been fitted to the exterior of hundreds of blocks built in the 1960s and 1970s to improve their appearance or insulation. Contractors at Grenfell Tower used a non-fire-resistant outer layer — a practice that isn't illegal under current British regulations.

Witnesses described chunks of the cladding raining down on the area surrounding the doomed high-rise.

They are removing the cladding from Chalcot estate in Camden pic.twitter.com/seVkjKRm6P — Girish Ch4 News (@GirishJuneja) June 22, 2017

Almost all the towers identified as featuring the similar cladding are owned by local governments and used as public housing, particularly for refugees or those on welfare.

May promised that "there will be nowhere to hide" for "any guilty parties."

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The disaster has triggered widespread anger.

"At least 79 people are dead — it is both a tragedy and an outrage because every single one of those deaths could and should have been avoided," opposition leader Jeremy Corbyn told the Parliament, saying working-class people had been “ignored.”

Matthew Needham-Laing, a litigation lawyer and expert in construction, told the BBC last week that video showing the fast-moving fire at Grenfell Tower was reminiscent of footage of recent blazes in Dubai where high-rise buildings were "engulfed in flames due to the cladding igniting."

Construction firm Rydon was hired to carry out an $11-million refurbishment at the London apartment block — a project which included adding "rainscreen" cladding. Rydon said the project "met all required building regulations."