Deadly Chengdu bus fire an act of arson?

Well, that's not being ruled out as a possibility. Witnesses being interviewed have said that they smelled gasoline just prior to the bus going up in flames. They said that someone had probably spilled something flammable. It also seems that the only thing that was flammable on the buses would have been the seats, but the burning pattern seems to suggest that it wasn't the seats that first caught on fire. Chinese commentary has suggested that the bus driver was at fault for 1. cramming too many people on the bus (he and every other bus driver in China) and 2. not stopping the bus when people saw flames coming out the back. It's going to be awhile before we know what happened—if we ever know. In the meantime, the blame game is on.