A teenage Japanese boy has been arrested after walking into a police station carrying a severed human head and claiming to have killed his mother.The 17-year-old went to a police station in the town of Aizuwakamatsu, north of Tokyo, carrying the head in a sports bag, Japanese media said.The beheaded body of a woman was later found at the boy's home, police said.This is the latest in a series of grisly killings in Japan, a country renowned for its low crime rate.
