Lee Chi-hang was born in 1954 in Hong Kong. Described as a quiet and academically underperforming individual, he exhibited unusual behavior and incoherent speech from a young age. In 1976, following a violent altercation with a neighbor, Lee was admitted to Castle Peak Hospital, a psychiatric institution, for six months. He later received treatment at the Yaumatei Psychiatric Centre. Lee suffered from depression and, during a family argument in January 1979, threatened to kill his parents. By 1982, he was unemployed and displayed signs of emotional instability.

On June 3, 1982, Lee Chi-hang committed one of the most disturbing mass stabbings in Hong Kong’s history. That day, he murdered his own mother and sister in their apartment at Un Chau Street Estate. He also attacked and wounded two other women in the same area. Then, in a horrifying escalation, Lee made his way to Anne Anne Kindergarten located nearby. Armed with a knife, he stormed into the school and began attacking the children inside.

Lee stabbed a total of 34 children. Tragically, four of them died from their injuries. Several teachers and staff members were also injured while trying to stop him. The chaotic and bloody scene shocked the community and drew heavy media attention. Police arrived at the scene and managed to subdue and arrest Lee.

Instead of going to trial in the conventional sense, Lee was evaluated and found to be criminally insane. Due to his mental condition, he was not convicted in court but was instead committed to a mental institution for an indefinite period.