A Japanese university professor who was attacked on campus last year has expressed mixed feelings about the death of a possible suspect in the case.

Miyadai Shinji of Tokyo Metropolitan University was stabbed by a man last November at the school's campus in Hachioji City.

The 63-year-old professor, who is a prominent sociologist, sustained serious injuries.

Investigators say a man identified as a possible suspect based on security camera images was found dead at a house in neighboring Kanagawa Prefecture. The man is suspected of killing himself.
Miyadai said in an online program on Wednesday that he was notified by police at around 9 a.m. that the man had died.

Miyadai also expressed relief that his family and others around him are no longer at risk of being harmed.

But he said he has doubts because the attacker's motive remains unknown, and he will have to go on without a solution to the case.

Miyadai said if the attacker's motive were known, people who express themselves could know what to watch out for, and society could have new information on what kind of motives people have.

He added that it's regrettable that both matters remain uncertain.