Newshub has obtained exclusive video of an overheating robot exploring the Pike River mine, taken just three months after a fatal explosion.
Twenty-nine miners died in the disaster and the Government has argued gas levels make it too dangerous to re-enter the mine to retrieve the bodies.
Until now, this video has been kept from the families of the 29 men killed, like Dean Dunbar, father of 17-year-old Joe Dunbar.
While the overheating robot can be seen emitting smoke or steam, there are no flames.
Watch the video for the full, unedited footage.