Four builders who were trapped inside a collapsed hydropower project tunnel more than a week ago were pulled out alive early on Tuesday in Yingjiang County, southwest China's Yunnan Province, Xinhua reported. The workers, who were dragged out this morning, were sent to the local hospital for checks. At 11:30 p.m. on Aug. 20, part of the water diversion tunnel for the four-tier hydropower plant being built on Daying River suddenly collapsed, trapping four workers who were working inside. Yunnan provincial, Dehong prefectural and Yingjiang county officials deployed more than 300 people for the joint rescue operation. Rescuers dug an extra passage to reach the trapped workers, while talking to them through a ventilation pipe, which also carried necessities such as food, drinkable water and first aid equipment to the trapped workers.