And land. Word of the great sept of baelor (basically equivalent to the Vatican ) getting blown the fuc up would spread. This show plays with time too so it's like some story lines are day to day while others seems to be longer times between scenes but anyway
Yeah I can see you saying how would they know Cersei is responsible but the queen of thornes knew it was her and being that most of the city hates her and knows she was supposed to be on trial that day and had ample reason to hate the church it would be likely that even the somewhat religious in a city of half a million would be blaming her