A fire aboard the number 842 bus in Shanghai’s Yangpu district during morning rush hour May 5 killed three people and injured a dozen more. The bus, operated by the Dazhong Transportation (Group) Co., caught fire around 9:15 a.m. local time near Huangxing Road and Guoshun Road. Publicly, security officials say the fire was an accident caused by a mechanical problem. However, security officials have privately said that an individual came on board the bus carrying flammable materials. There is strong suspicion that the fire was the result of an intentional act, perhaps related to someone frustrated with losses on...