The Chinese Premier, Mr Zhu Rongji, has denied that the explosion at a primary school in East China was a result of an illegal fireworks factory operated by the children.
Local officials confirmed yesterday that using schools as firework factories was rife in the area, where at least 43 children and adults were killed on Tuesday, but Mr Zhu claimed the explosion was the work of a deranged man.
Third-grade pupils were said to make fireworks to earn extra money for the cash-strapped Fanglin elementary school in Jiangxi province's Wanzai county, where the blast flattened four classrooms.
"It's such a common phenomenon here. It happens to every school in every village and every county," one school official in Wanzai county said.
State media reported that children were fingering explosives and detonators at the time of the blast. While they claimed that the official number dead was 43, 39 children and four adults, reports from the village suggest the figure was higher.
However, speaking to Hong Kong reporters on the fringes of the National People's Congress in Beijing yesterday, Premier Zhu dismissed the firework reports.
"Certainly it's not the case that this primary school was trying to earn some money by renting out space to store materials for fireworks," he said. "I was most worried that it could have been that. Now investigations show it's not that."
Mr Zhu said a deranged man with grievances and who had mental illness was to blame.
There was anger in the village and outrage abroad that children of eight or nine were making firecrackers at school. It was reported that relatives of the dead were so furious that troops had to intervene to prevent attacks on the local county boss.
UNICEF, the United Nations children's fund, said yesterday it was outraged by the disaster. "Our outrage is directed at school officials who allegedly forced the children, as young as eight, to assemble fireworks on school grounds," it said in a statement. "Exploitative child labour of any form is morally unacceptable and a violation of children's rights."
Officials in the region said families of the victims would receive 30,000 yuan (about £3,000) from the government and 2,000 yuan (about £2,000) from an insurance company. A Foreign Ministry spokesman said that the central government deplored child labour, adding: "To hire child labour is a serious criminal act in China."