Arrested stepfather talks about killing boy

Police on Thursday arrested the stepfather of a 9-year-old boy who was found dead on suspicion of abandoning a body. The man has admitted to the killing, allegedly saying he became mad when the stepson talked back to him and called him "not his biological father."

Ryosuke Shindo's body was found in the predawn hours of Wednesday on the grounds of the apartment building in which his family lives in Saitama Prefecture, north of Tokyo. He had been strangled to death.

Police say the suspect, Yusuke Shindo, told them what drove him to commit the act. The 32-year-old man allegedly said he told the boy to search for a cap he had lost, but that the stepson replied, "Leave me alone, you are not my biological father."

The police suspect that the crime may have been impulsive. They say there was no evidence the boy had been abused.