Two students died and 20 others were injured in a stampede at a primary school in central China's Henan Province, state media said on Wednesday.
The accident happened at the Number Three Experimental Primary School in Puyang county as some students rushed into the bathroom in the morning break.
Another report claimed panic broke out after the toilet's wall collapsed.
The authorities in Puyang county said the incident is under investigation.
All the injured students have been taken to nearby hospitals.
Overcrowding and poor building design and construction have been blamed for past crushing deaths and injuries at Chinese schools.
Other safety problems have included the use of running tracks made from scrap that made students sick due to noxious fumes.
China's deadliest stampede incident in recent years came during New Year festivities on Jan. 1, 2015, when 36 people died in a crush along Shanghai's riverfront esplanade.