Several high school students taking their university entrance test in Tokyo were injured in an alleged knife assault on Saturday, according to Japanese media.

According to NHK, three persons were conscious after being hurt in the morning by another student who assaulted them with a bladed item as they gathered to take their entrance exam.

According to the Asahi newspaper, the suspected attacker, a 17-year-old high school student, was apprehended.

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.