In February, Masafumi Yamagishi, a 2-year-old resident of Edogawa Ward, was found bleeding and collapsed. The Tokyo Metropolitan Police Department arrested Kosuke Omoto, 63, on suspicion of murder.

Omoto told a voluntary interview before his arrest that he was at school at the time of the incident. Police are investigating the possibility that he attempted to create an alibi while working at the school around the time the incident occurred. The teacher assumed that the investigation would be extended, police say.