Rescuers digging through rubble of tunnel at Freeport's mine in Indonesia to reach 23 trapped

TIMIKA, Indonesia – Rescuers were digging for a fourth day Friday trying to reach 23 workers trapped in a caved-in tunnel at a giant U.S.-owned gold and copper mine in Indonesia.

PT Freeport Indonesia, the operator of the Grasberg mine in Papua province, said rescuers had successfully cleared two passages to provide access for heavy equipment that will help expedite the rescue efforts.

The collapse happened Tuesday when 38 workers were undergoing safety training inside a classroom in the tunnel, which is part of a training facility located away from where normal mining takes place. Ten workers have been rescued and five bodies recovered since then.

More than 20,000 workers are employed at the mine owned by Phoenix, Arizona-based Freeport-McMoRan Copper & Gold Inc. in the restive province, which holds some of the world’s largest gold and copper reserves.

Until Friday, rescuers were manually removing debris since heavy equipment could not fit in the tight space.

Papua Governor Lukas Enembe visited the scene Friday and estimated that rescuers might need two to three days to get through the classroom.

“Since it is the most fatal accident in Freeport history here, we surely take it into account as a pressure to guarantee safety of the workers,” Enembe said.

PT Freeport Indonesia revised the number of workers believed to be trapped to 23 from 24 after one of them was discovered to have escaped unharmed.

Hundreds of workers are still blocking a main road about 3 kilometres (1.8 miles) from the accident site in solidarity with the victims. They are seeking a guarantee from management that they will be safe working underground.

President Susilo Bambang Yudhoyono has ordered both Freeport and concerned government agencies to intensify rescue efforts and to thoroughly investigate the accident.

In 2011, production at the mine was crippled when 8,000 unionized employees walked off the job after demanding higher pay. The strike ended after the company agreed to a 37 per cent wage hike and improved benefits.