Rescue workers and all those present at the site of the accident at Da Dang-Da Chomo hydropower plant burst into tears - for joy, when 12 alive victims were brought out from the collapsed tunnel where they had been trapped for 81 hours.

At 4:30 pm on December 19, the victims one by one appeared at the tunnel mouth, some walking by themselves and some on stretchers.

The tunnel at the hydro power plant in Lat commune, Lac Duong district, Central Highlands Lam Dong province, caved in at 7:30am of December 16 when 32 workers were inside to do their job. Only 20 were able to escape outside, while 12, including a woman, were trapped inside, separated from the outside world by a 35m-long mass of stone and soil.

A trapped worker is carried out of the tunnel (Photo:Vnexpress)

The section is about 500 metres from the opening of the 720m-long tunnel running though the mountain to bring water to the plant.

Colonel Nguyen Huu Hung, Deputy Chief of Staff of the Defence Ministry’s Arm of Sappers and commander of rescue efforts at the site, said rescuers started digging a small tunnel to the left of the collapsed one on December 18. Luckily, they reached the section behind the collapsed portion after digging only 14 metres.

Earlier, they planned to dig two tunnels on both sides of the collapsed one to rescue the victims, he added.

Lieutenant Nguyen Van Tien from Battalion 32 of the Arm of Sappers’ Brigade 293 was the first person to meet the trapped workers.

He said after successfully reaching the section where the workers were stranded, rescuers waded through water for some 20 metres deep into the tunnel and shouted for the victims. Then they heard a cry for help and saw a worker walking to them.

Earlier, rescue forces drilled several holes into the tunnel to pump oxygen and provide food, clothes, and other items to support the victims. More than 500 people were involved in the rescue mission.

Work on the Da Dang-Da Chomo project in Lac Duong district kicked off in 2003. The 475 billion VND (22.6 million USD) plant, invested by the Civil Engineering Construction Corp. No. 5 (CIENCO 5), is designed to have a capacity of 22 MW.