British authorities say 34 high-rise apartment blocks across the country have been found to have cladding that fails fire safety tests ordered after the Grenfell Tower disaster.

Meanwhile, council officials in London scrambled to evacuate four public housing towers after experts found them “not safe for people to sleep in overnight.”

Hundreds of residents hastily packed their bags and sought emergency shelter, with many angry and confused about the chaotic situation.

Some refused to leave their apartments. Scores of evacuees slept on inflatable beds in a gym while officials sought better accommodation for them.

Camden Council leader Georgia Gould said the council decided to evacuate the blocks in north London’s Chalcots Estate late on Friday after fire inspectors uncovered problems with “gas insulation and door stops”.

That, combined with the presence of flammable cladding encasing the buildings, meant residents had to leave immediately, she said.

The evacuation comes amid widening worries about the safety of high-rise apartment blocks across the country following the inferno that engulfed Grenfell Tower on June 14, killing at least 79 people.

Attention has focused on the 24-story tower’s external cladding material, which has been blamed for the rapid spread of that blaze, but multiple other fire risks have now been identified in some housing blocks.

The government said on Saturday that the cladding samples that failed fire safety tests came from 34 apartment towers in cities including London, Manchester, Plymouth and Portsmouth.

Camden Council leader Georgia Gould is confronted by one of the hundreds of residents evacuated from Chalcots Estate in London.

So far, Camden Council has been the only local authority to have asked residents to leave as a precaution. It said about 650 apartments were evacuated.

The council said residents would be out of their homes for three to four weeks while it completes fire-safety upgrades.

“I know some residents are angry and upset, but I want to be very clear that Camden Council acted to protect them,” Gould said in a statement.

“Grenfell changed everything, and when told our blocks were unsafe to remain in, we acted.”

Renee Williams, 90, who has lived in Taplow Tower since 1968, told Britain’s Press Association: “No official came and told us what’s going on. I saw it on the TV, so I packed an overnight bag.

“It’s unbelievable. I understand that it’s for our safety but they can’t just ask us to evacuate with such short notice. There’s no organisation and it’s chaos,” she said.

If all fire-prone cladding panels is stripped from the evacuated towers, this is what they will look like.

Prime Minister Theresa May, who has been criticised for her slow response to the Grenfell tragedy, said the government was supporting Camden officials to ensure residents had somewhere to stay.

Opposition Leader Jeremy Corbyn said May needed to “get a grip” and lead a stronger response to what is a “national threat.”

Police said on Friday they were considering filing manslaughter charges in the Grenfell disaster and will look at everything that contributed to it.

Detective Superintendent Fiona McCormack told reporters, “We are looking at all health and safety and fire safety offenses, and we are reviewing every company at the moment involved in the building and refurbishment of Grenfell Tower.”

The government has ordered an immediate examination of the refrigerator model that started the blaze, the Hotpoint model FF175BP refrigerator-freezer.