A metro worker remained missing by 4 pm Thursday after an accident at a construction site in Qingdao, Shandong provinc collapsed, according to a post from Qingdao Metro's official WeChat account.
The accident was caused by a building collapse that opened a 10-meter diameter hole in the ground through which the missing worker fell, said the post, adding that search and rescue work is underway. No workers were working underground at the time of the accident.
The accident brings more controversy to Qingdao Metro following a recent project scandal.
A former contractor involved in power supply work at the metro told media that the construction had been substandard and could potentially cause safety hazards, China Central Television reported last week.
After an investigation, Qingdao Metro announced on Friday that they had found problems involving the uneven laying of steel bars and an uneven thickness of concrete cushion. The company has blacklisted those responsible and decided to rebuild the project to ensure its safety.
The collapse on Thursday occurred one month since this scandal. On May 27, another building collapse left five workers dead.
