TOKYO, Reuters – A knife attack left several high school students in Tokyo with injuries on Saturday. Japanese media reported that the incident occurred.

NHK Public Broadcasting reported that the incident occurred when a student beat three of its students with a knife as they stood to take their entrance exams.

According to the Asahi newspaper, the alleged attacker, a high school student aged 17, was taken into custody.

A half million Japanese high school students are taking annual university entrance tests this weekend at hundreds of locations across Japan.

Tokyo’s Metropolitan Police Department stated that it was unable to comment on details or confirm arrests.

Although violent crimes in Japan are rare, there has been an increase in knife attacks from unknown assailants.

On October 10, a man in Batman’s Joker attire stabbed over a dozen passengers on a Tokyo train. This sent commuters running up the train tracks, screaming, and forced them to jump out of their windows. A knife attack by a Tokyo commuter railman left several injured months prior.