A government agency said it would not identify the buildings with combustible panels until landlords have had the opportunity to notify residents.
The attack was being investigated as a terrorist act that targeted Muslims, who were leaving evening prayers during Ramadan.
Public anger is mounting as residents, neighbors demand answers for how the fire spread so quickly, trapping many of the tower’s 600-some residents.
Whole families are missing, and the death toll is certain to rise after flames tore through the 120-unit Grenfell Tower as many slept early Wednesday.
The blaze early Wednesday in the 24-story building in west London’s North Kensington district also injured 79 others, 18 of them critically.
The cause of the fire is not yet known, the London Fire Brigade said.
Flames and smoke were still shooting from the windows of the Grenfell Tower in North Kensington more than 4 hours after the blaze started around 1 a.m