Later that night, his body was found by another student at the foot of the dormitory block.
The statement described it as “an accident where a student fell from a height at school”. It added that the police had conducted investigations and an autopsy, and “at present exclude it as a criminal case”.
But allegations have swirled online for days that there was more to the story and that the school and authorities were hiding the truth. One account claimed, without proof, that Dang killed himself after he was bullied by the boy he’d fought with earlier.
Unverified remarks from his family have been circulating, alleging that the injuries on Dang’s body were inconsistent with the authorities’ version of events and that they were not allowed to examine his body for long.
The allegations appeared to have incensed many in Pucheng, sparking protests that drew at least hundreds of people.
Bullying has become a highly sensitive topic in China in recent years, with past cases of student deaths triggering protests. Last month, a Chinese court handed out lengthy jail sentences to two teenagers who murdered a classmate.
There are also videos posted on X on Monday, which the BBC has confirmed were filmed at the Pucheng Vocational Education Centre, showing people mourning the teenager’s death. They placed flowers and offerings at the entrance of the school, and conducted a traditional mourning ritual by throwing pieces of paper from the rooftop of a school building.
Other videos circulating online appear to show demonstrators, many of them young, storming a building and clashing with police while shouting “give us the truth”.
One verified clip shows a school official confronted by shouting protesters who shove him around. Others show destroyed offices in the compound, and protesters pushing down a barricade at the school entrance.
Another show protesters hurling objects such as traffic cones at groups of retreating police; and officers tackling and detaining people while beating them with batons. Some protesters are seen with blood on their heads and faces.
There is little information on what happened next, but reports on social media suggest a much larger police presence in Pucheng in recent days with no more reports of demonstrations.
Authorities have also urged the public not to “create rumours, believe in rumours, or spread rumours”.