Rescuers try to help a stranded student out of the debris at Wudu Primary School at Hanwang town in Mianzhu city, Sichuan Province, 13 May 2008 (photo released by Xinhua news agency)

Some 900 students were trapped in the wreckage of Juyuan Middle School in China's Sichuan province after Monday's earthquake. Most are now presumed dead.

Workers have recovered dozens of bodies and a few survivors from the rubble - but hundreds remain buried.

Since the earthquake, the wreckage of the school has been surrounded by anguished family members, who set off firecrackers, according to tradition, to mark the sad event. Overnight rains turned the schoolyard to mud as parents lit candles and waited for news of their children.

Some bystanders called out to emergency workers, weeping and asking them to hurry as they picked through the debris with tools. Recovered corpses were laid out on the ground for identification.

Because other buildings in Juyuan were left standing, the disaster has raised questions about the quality of the school's construction.

Some information for this report was provided by AP.