Zhang Xiangdong, 46, receives treatment at a hospital in Yichun, Jiangxi province, on Friday. He was injured in the collapse of a power plant construction platform in Yichun, Jiangxi, on Thursday morning. Thirteen people have been detained for questioning about the accident. Provided to China Daily and Hu Chenhuan / Xinhua

Illegal subcontracting of engineering in construction projects will also be targeted, the authorities said.

"Local authorities should conduct serious investigations, and ensure that each construction site accident is investigated and treated in accordance with the law," it said.

According to Yichun officials, construction of the power plant, which belongs to Jiangxi Ganneng Co, began in July last year and was expected to be completed by early 2018.

The accident at Fengcheng Power Plant is the most serious in China since a landslide at a waste dump in Shenzhen, Guangdong province, buried buildings last year, killing 73.

Wang Yaosheng, a worker at the Fengcheng construction site who escaped unscathed, said dozens of workers were on the 70-meter-high scaffolding when the platform collapsed.

"We heard people shouting from above. Then the scaffolding started to collapse, hitting the water tower and the emergency exit," he told China Central Television.

Workers on the ground, including Wang, ran from the cooling tower. Within minutes, the scaffolding and work platform collapsed, he said.