Six people died and three were injured Wednesday after a construction site collapse in east China's Shandong Province, said local authorities Thursday.

The accident happened at around 10 p.m. Wednesday when a newly-built concrete work platform and scaffolding of an underground construction collapsed at Qiujiadian Town, Taishan District, in Tai'an City, according to a spokesman with the district government.

Six construction workers, who fell from the 15-meter-high platform, were taken to hospital, where three of them died later.

Three others were buried under the unset concrete in the pit after the collapse. Their bodies had been recovered, said the spokesman.

The three injured, who were still receiving medical treatment at the No. 88 Hospital of the Chinese People's Liberation Army, were out of danger, he said.

Police are investigating the cause of the accident.

Source: Xinhua