A robot sent into the Pike River coal mine has found a miner's hat with the light still on. Footage taken underground will be shown to families at 4pm.

If you haven't got time to read all our in-depth coverage of the Pike River Mine disaster, here's a quick summary of five key things you need to know today.

Families at this morning's Pike River briefing were unhappy they were not shown blast footage until yesterday, a miner's father says.

Dramatic security camera film has revealed the scale of Friday's Pike River mine blast.

The only sign that the Pike River boss is feeling the strain are the dark bags under his eyes which sag lower by the day.

"They don't understand it fully. For them, it's 'Dad's on a holiday' or 'he's just stuck underground'.

The robot sent into the Pike River Mine was operating outside of its primary role when it broke down.

The Police Commissioner Howard Broad echoed the feelings of all involved in the Pike River disaster, as it was revealed drilling on the mine bore hole was still hours from completion.

Families have viewed footage of the Pike River mine blast this afternoon. Lawrie Drew, father of Zen Drew, said the footage was difficult to watch.

Signs have been erected around Greymouth in support of the 29 miners and contractors trapped in the Pike River mine.

Sending a robot into the Pike River coal mine where 29 men are trapped was always a "long shot", an expert says.

New Zealand Oil & Gas has shed as much as a third of its market value when the shares resumed trading this afternoon after being halted for the Pike River Coal mine explosion.

After learning his stepson was one of the 29 trapped miners, Stephen Rose began carrying a 'worry stone' around with him.

"The families are frustrated, we are frustrated, the country is frustrated," John Key said after four days of waiting for a rescue effort.

The level of toxic gas in the Pike River mine is still too high after for rescuers to be sent in.

A robot sent into the Pike River mine malfunctioned when water fell onto it.

Pike River Coal says work on evaluating the impact on its West Coast mine of Friday's explosion is "down the line", as it focuses for now on finding the 29 men unaccounted for.

If you haven't got time to read all our in-depth coverage of the Pike River Mine disaster, here's a quick summary of five key things you need to know today.

The families of 29 trapped men trapped after the Pike River mine blast are being updated on progress.

The sun smiled on Greymouth yesterday, but faces were grim and the sadness here was palpable.

The day before he went down the mine for the first time, Joseph Dunbar turned 17.

Seventy-two hours on, mining officials and police have conceded they are preparing for the worst.

A scientist says temperatures inside the Pike River mine may have soared higher than 1200C during the blast.