A high school student in Kawasaki near Tokyo was stabbed on his way to school on Monday, with a minor who knows the victim arrested the same day on suspicion of attempted murder, police said.
The 16-year-old student's injuries are not life-threatening, the Kanagawa prefectural police said. The attacker fled the scene.
According to investigative sources, the suspect, also 16, is a former schoolmate of the victim but is now studying at a different high school.
The suspect, who is from Kawasaki, denied the allegation.
The police are investigating whether he had a grudge against the hospitalized boy, who lives in Tokyo's Setagaya Ward.
The student was walking to school at about 8:20 a.m. when he was attacked with a knife in a residential area in Kawasaki's Asao Ward, sustaining injuries on the back of his head.
There were no signs of an altercation before the incident, and an eyewitness reported seeing the attacker leave the scene on foot, the police said.
A knife that appears to have been used in the attack was found at the scene, the police said.
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