School officials in Toride, Ibaraki Prefecture, looking into the 2015 death of a 15-year-old schoolgirl concealed the fact that she committed suicide while surveying her classmates and parents, it has been learned.

The family of Naoko Nakashima, who was a third-year student at a junior high school in Toride, claims that the concealment of such key information led the school and the Toride Board of Education to wrongly conclude she had not been bullied.

According to the board of education, Nakashima hanged herself at home on Nov. 10, 2015. Her diary had an entry that read, "I don't want to be bullied."