A small plane crashed into a residential area of Tokyo on Sunday, setting fire to several houses and reportedly killing three people and injuring five others, according to officials as well as local media.At least three houses and two cars were on fire in the capital`s residential district of Chofu by the crash, which also damaged the roofs of other houses nearby, NHK said.Police have launched an investigation into the accident on suspicion of professional negligence resulting in death, local media said.Television footage showed firefighters battling the inferno.