Looks like the building got shelled by a heavy vehicle judging from the locations and sizes of the impacts and a very large fire broke out. Lots of different types of shells,,,many with pyro elements and high explosives, but even sparks can start a fire. Who knows. Bad things happen when rich people use poor people.
The blast radius of the mysterious Hunga Tonga blast was at least 3x that of Tsar Bomba…so around 9x more powerful. Likely much more so considering subsea vs airburst.