Rescuers work at a collapsed mine in Pingyi County, East China's Shandong Province, Jan 6, 2016. Rescuers managed to dig more than 200 meters down into the shaft of the collapsed mine on Monday, but found no new survivors. [Photo/Xinhua]

Previous successful cases of its kind

In Chile, Oct 2010

On August 5, 2010, 33 miners became trapped when Chile's San Jose mine collapsed. A total of 69 days later, all the miners were pulled from the mine alive.

The miners were trapped 700 meters underground and about 5 kilometers from the mine's entrance via spiraling underground service ramps.

The mixed crew of experienced miners and technical support personnel, with less experience working underground, survived for a record 69 days deep underground before their rescue.

A 5-inch wide hole became their lifeline, a vessel for food, water and supplies.

In the US, July 2002

On July 24, 2002, a work crew of nine men from the Quecreek Coal Mine in Somerset Pennsylvania inadvertently drilled into the adjacent abandoned Saxman Mine, liberating an estimated 50-60 million gallons of water into the active mine. The men were trapped in an air pocket within a 48-52 inch coal seam 240 feet underground for more than 3 days.

The rescuers started drilling a rescue shaft large enough for a rescue capsule to be lowered to the miners.

On the 28th of July, all nine men were retrieved safely from the mine.