Pike River says equipment such as robots could create sparks in a gaseous environment.

Testing of gas levels in the Pike River mine continued overnight, but the mine is still deemed too dangerous for a rescue attempt to be mounted.

Rescuers are on standby to enter the Pike River coal mine to bring out their brothers, and will go in at the slightest opportunity.

Rescue workers, who have one of their own trapped in the Pike River coal mine, hope a hole being drilled in the mine tonight will reveal air samples allowing them to enter the mine.

These photos tell the story of this tragic event, and of its impact on those involved.

It's been revealed a member of the mine rescue team is among those trapped. Officials say gas levels inside the mine are falling, but unstable.

The backgrounds of the missing men are as wide and varied as their ages, hailing from as far abroad as Scotland and Africa. Meet the miners.

The Pike River mine blast has made global headlines, with two Britons, two Australians and a South African are among the 29 missing.

Praying for a miracle, hundreds attended church services in Greymouth on Sunday morning.

Families of the 29 men trapped in the Pike River coal mine near Greymouth on the West Coast are being taken to the site.

While residents gather and families worry, hospital staff and funeral directors prepare themselves for all scenarios.

International mining experts have raised concerns about safety issues at Pike River Coal which may have led to the explosion.

West Coasters are known for their fighting spirit, which has been tested to the extreme this weekend.

A second night passes with no word from the 29 trapped miners in the Pike River mine. Families cling to hope as experts fear the worst.

There will be no attempt to rescue 29 miners trapped in a West Coast mine tonight, with no further air quality sampling until tomorrow.