A community resident told the Beijing Youth Daily that the fire started at 9:00 p.m. on the 2nd. After the fire came out, it soon rushed to the top. There are residents and some offices in this building, which is more than 20 floors. Usually, there are people working in it. Residents of the community said that by 23:20, the fire outside the building had been basically put out, but the fire could still be seen through the windows inside the building.
Source: beiqing.com - editor in charge of Beijing Youth Daily: Dai Wenjia, nb12498