A 14-year-old junior high school student died after being stabbed Wednesday by another student at his school in Aichi Prefecture, local police said, and an investigation is underway on whether the two had been involved in an altercation.

The police arrested the alleged attacker, also 14. He has admitted to stabbing his schoolmate, Yuzuki Ito, the police said. The police said they confiscated a 20-centimeter-long kitchen knife that was used in the attack.

The suspect allegedly stabbed Ito in the stomach at around 8 a.m. at Jushiyama Junior High School in the city of Yatomi, with the intent of killing him, the police said.