LONDON — The doorbell woke Yassin Adam just before 1 a.m. A neighbor was frantically alerting others on the fourth floor of Grenfell Tower about a fire in his apartment. “My fridge blew up,” the man shouted.

Residents of Grenfell Tower had complained for years that the 24-story public housing block invited catastrophe. It lacked fire alarms, sprinklers and a fire escape. It had only a single staircase. And there were concerns about a new aluminum facade that was supposed to improve the building — but was now whisking the flames skyward.

The facade, Mr. Adam said, “burned like a fire that you pour petrol on.”

The incineration of Grenfell Tower on June 14, the deadliest fire in Britain in more than a century, is now a national tragedy. The London police on Friday blamed flammable materials used in the facade for the spread of the blaze and said the investigation could bring charges of manslaughter. Hundreds of families were evacuated from five high-rises that posed similar risks.

Flames consumed the tower so quickly that arriving firefighters wondered if they could even get inside. People trapped on the higher floors screamed for their lives through broken windows. At least 79 people died, a toll that is expected to rise as more bodies are recovered. Survivors have charged that the facade was installed to beautify their housing project for the benefit of wealthy neighbors.