Several high school students sitting their university entrance exam in Tokyo were wounded on Saturday in an apparent knife attack, Japanese media said, Trend reports citing Reuters.
Public broadcaster NHK said three people were conscious after being injured in the morning when another student attacked them with a bladed object as they gathered to take their entrance exam.
The alleged assailant, a 17-year old high school student, was arrested, the Asahi newspaper said.
Half a million high school students across Japan are taking the annual university entrance exams this weekend in hundreds of venues across the country.
Tokyo's Metropolitan Police Department said it could not comment on the details of the attack nor confirm any arrests.