​One early morning at 4:24, in Hangzhou Mingxu Jinghuili, a smoke alarm immediately caught the attention of Zhou Xiaofeng, the on-duty staff at the fire control room, who promptly asked the patroller Wang Hongjun to check the situation. Wang Hongjun soon arrived at the scene and knocked on the door, however, no one answered the door. He carefully inspected the surroundings and did detect a faint smell of smoke from indoors. So, he continued knocking and called the foreman Li Ke for assistance.