Mourners gathered outside the school, leaving flowers and cups of milk tea at the gate. A young couple placed white flowers before bowing their heads in prayer as others continued to arrive throughout the day.

Investigators said the teenager fired at least 26 rounds from a handgun belonging to his grandfather. Authorities said he had earlier killed his grandparents at their home before travelling to the school and opening fire.

The death of the 12-year-old brought the overall death toll to nine, including the suspected gunman and his grandparents. Twenty-three people were initially reported injured.

Police are continuing to investigate the shooting, including how the teenager gained access to the firearm.