Rescuers have drilled through to the main tunnel at the New Zealand coal mine where 29 miners were caught in a methane-fuelled explosion last week.
They have not been heard from since.
The drill hole, reaching 530 feet into the mine, has broken through, causing “hot air and gases to rush up,” Pike River Coal chairman John Dow said.
Rescuers began immediately sampling gas rising from the hole, located near where some miners were working when the blast happened on Friday.
Rescuers plan to put a video camera down the hole to look for signs of the missing miners.