A 17-year-old high school student has been arrested for stabbing his mother and grandmother with a kitchen knife at their home in Gobo City, Wakayama Prefecture, police said Friday.

According to police, the youth stabbed his mother in the back, using a knife with a 30-cm blade, as she slept at around 3:30 a.m. on Thursday, Sankei Shimbun reported. He then stabbed his 82-year-old grandmother who was found in the toilet, bleeding from a knife wound to her chest.

The boy then called 110 and said someone had stabbed his mother and grandmother. The two women were taken to hospital and in a stable condition, police said.

Police said the boy has confessed to the crime and was quoted as saying, "I was frustrated with the way they were always disciplining me."

Officials at the boy's schools said he was a great student and was actively engaged in a club activities. They said they had no idea about his home life.

© Japan Today