Thirty-three primary school students in Changsha, the capital of Central China's Hunan province, were injured after an accident on Wednesday.

Thirty-one students have been released from hospital, while two are still receiving medical care, the China News Service reported.

The accident happened at around 11 am at the Yuying No 2 Primary School.

A group of students went to the playground during their break but found that the playground was flooded, so they decided to return to their classrooms.

When they were climbing the stairs they encountered another group of students coming down. In the ensuing confusion, some students fell, were stepped on and suffered injuries, the report said.

The school principal Yan Chunlin said that the school will cover the costs of the medical treatment.