The so-called "rat miners" are adept at burrowing in tight spaces.

Half a dozen of them started working late Monday, after a second drilling machine broke down with 15 meters left to reach the trapped men.

Working for more than 24 hours, they split up into two teams of three, with one person drilling, the second collecting the debris and the third pushing it out of the pipe.

And on Tuesday, rescuers successfully pulled out the workers after a 17-day ordeal.

"Rat-hole" mining is a dangerous and controversial method used to extract thin seams of coal.

The name comes from its resemblance to rats digging pits into the ground.

The pits are just big enough for workers, often children, to descend using ropes or ladders to extract coal - often without safety measures and proper ventilation.

The practice became illegal in the 1970s, when India nationalized coal mines and gave state-run Coal India a monopoly. But many small mine owners continued to employ short people or children in "rat-hole" mining, and federal authorities didn't interfere.

It was used extensively in the northeastern state of Meghalaya before it was banned by an environmental court in 2014.

At least 15 miners were killed in one such "rat hole" mine in Meghalaya after being trapped for more than a month until January 2019.