Rescuers created an emergency air vent for a group of over 20 workers trapped in an under-construction expressway tunnel that collapsed Friday in China's Fujian province.
The workers were trapped after "a 30-metre-long section of the expressway tunnel in Longyan City collapsed", a rescue official told Xinhua.
The trapped workers confirmed the vent's success by knocking on the 27-metre-long iron tube.
An estimated 5,000 cubic metres of debris was blocking the tunnel, which was being expanded to accommodate the expressway linking Xiamen city of Fujian and Chengdu, capital of southwest China's Sichuan province.
While the rescue operation was still underway, there was no immediate information about any casualty.
