Andy, I looked up Grenfell Tower in London. There are certain conditions under which a concrete building will burn, especially if there are things inside which will burn. It appears to be more complex than I thought. My feeling was that with all the gas in the cars, the city would burn.

Glass would certainly break, plus while all the concrete wouldn't burn, the furniture and everything else inside would.

https://grenfellenquirer.blog/2020/08/30/grenfell-tower-fire-questions-answers/#