LONDON (CNN) -- Initial tests on cladding in a number of tower blocks in London have come back as combustible, British Prime Minister Theresa May told the House of Commons Thursday during a statement about last week's fatal Grenfell Tower blaze.
May said that at least 100 buildings a day are being tested and that residents will be informed of the findings. She added that the authorities and fire services are working to ensure their buildings remain safe.
The Prime Minister also told Parliament that the Grenfell Tower block cladding is being tested and a statement is expected to be made by police and fire services in the next 48 hours.
At least 79 people are dead or missing and presumed dead following the blaze that tore through the 24-story high-rise, home to 125 families, in the early hours of June 14.
May said that 151 homes were destroyed in the fire. She added that 164 properties have been found to rehouse residents and are currently undergoing inspection.
"I know many others living in tall residential buildings will have concerns about their safety after what happened at Grenfell," May said.
"All social landlords have been instructed to carry out additional fire safety checks on tower blocks and ensure the appropriate safety and response measures are in place."
"We've also taken steps to make private landlords aware and make our checking facilities available to them for free."
Council chief resigns
Earlier Thursday, the chief executive of Kensington and Chelsea council, where Grenfell Tower is located, resigned from his post.
Nicholas Holgate said that he had been asked to step down from his role by Communities Secretary, Sajid Javid.
His resignation, which was welcomed by the Prime Minister, comes after accusations that the council failed to deal with the aftermath of the disaster.