At least 67 people died in a scaffolding collapse at a power plant construction site in China’s Jiangxi province on Thursday, China's Xinhua news agency reported.
Deadly accidents are relatively common at industrial sites in China, where anger over lax standards is growing. Three decades of swift economic growth have been marred by incidents ranging from mining disasters to factory fires.
The accident occurred at the Ganneng Fengcheng power station after a platform at a cooling tower collapsed with workers inside. The death toll is likely to rise as some workers remain trapped under the rubble.
State television, which put the death toll at 67, said rescuers were trying to free one trapped worker.
Chinese Premier Li Keqiang has ordered an investigation, demanding that those responsible for the accident should be held accountable, the central government said.
"Strengthen supervision and preventive measures, prevent such a major accident from happening again," it cited Li as saying in a statement on its website.
A total of 32 fire trucks and 212 military personnel have been deployed to the scene as rescue efforts continue.
Pictures from the scene show a grey mass of concrete slabs, steel girders and twisted metal splayed in a heap on the ground inside a large round structure.
Xinhua did not identify the type of power plant, but previous state media reports have said it was coal-powered.
China has vowed to improve safety at such facilities. President Xi Jinping has said authorities would learn the lessons paid for with blood after chemical blasts in the port city of Tianjin killed more than 170 people last year.
In August, a pipeline explosion at a coal-fired power plant in the neighbouring province of Hubei killed 21.