Sasebo slashing

The was the murder of a 12-year-old Japanese schoolgirl, , by an 11-year-old female classmate known as "Girl A". 
The murder happened on June 1, 2004, at an elementary school located in Higashiokubocho, Sasebo, Nagasaki Prefecture. The murderer slit Mitarai's throat and arms with a box cutter.
The slashing became an Internet memes and led to people talk about lowering the age of criminal responsibility in Japan. The killer's real name has not been released to the press. 
The murderer was nicknamed "Nevada-tan" because a class photograph showed a girl believed to be her wearing a University of Nevada, Reno sweatshirt.
However, the girl's real name was accidentally revealed on a Fuji TV broadcast and members of Japanese internet community 2channel further publicized her identity on June 18, 2004.