Families of the 29 men who died in the Pike River mine continue to be frustrated that the recovery of the bodies is still not underway.
A massive fire, with flames shooting through a mine shaft, continues to burn in the mine.
Among the grim news the families were told this evening was that the gag jet engine designed to stop the fire and allow recovery teams in to retrieve the bodies would now not be activated until tomorrow morning, despite being at the scene today.
Grey District Mayor Tony Kokshoorn said there was "total silence" from the families when they were given the latest update.
"They're totally subdued and they're desperate now," he told 3News.
"How long do they have to wait to get their loved ones out of there?"
The entrance to the mine has been sealed, ready for the gag to begin work tomorrow, Mr Kokshoorn said.
The families were shown "graphic footage" of flames leaping from the mine's shaft, with bolts sheared off.
"So there's some tremendous forces in that mine. You just wouldn't wish it on anyone."
Despite the fire, the families had been told there was still hope of getting the men's bodies out of the mine, he said.
"If they can put the gag in place, they've got the nitrogen they need to put the fire out, they've got the avgas here - the air force brought it in - it's all in place, they just need to set it up and get it moving," Mr Kokshoorn said.
An earlier report of a fifth explosion was incorrect, a Pike River mine spokesman told NZPA.
JUDGE TO LEAD INQUIRY
High Court judge Justice Graham Panckhurst will lead a Royal Commission of Inquiry into the Pike River disaster.
Prime Minister John Key this afternoon announced details of the inquiry.
Mr Key has also announced that an international mining expert would be recruited by the Department of Labour to carry out an urgent audit of all underground mining in New Zealand.
He said Justice Panckhurst, a sitting High Court judge, would be joined by two others with expertise in mining safety and regulation. They would be announced later.
The inquiry would have a wide scope, covering the cause of the explosion, the cause of loss of life, the search and rescue operation, the systems at the mine and relevant regulatory rules in the mining industry.
It would start work as soon as possible and the cost would run into millions of dollars.
"Royal Commissions are reserved for matters of very significant public interest and the Pike River mine tragedy is one of those," Key said.
The terms of reference were only a draft and would be finalised after the commission was appointed and met.
There would be wide involvement from families and the industry and commissioners would have to spend a lot of time on the West Coast.
There was a chance the commission would be delayed by other inquiries it could not conflict with.
Brenda Rackley, partner of John Hale, one of the miners who perished, said friends and relatives were desperate for answers.
She welcomed the inquiry, and said she could not understand how the men had died in a mine less than two years old.
"I can't get it around my head that they had the best technology in the world ... I've been asking myself how this could happen."
Rackley said Hale had often expressed concern about the mine's safety.
She hoped the inquiry would investigate near-misses and other safety incidents in the mine's history.
Grey District mayor Tony Kokshoorn called for transparency, truth and honesty and said the inquiry was the way to get it.
"It's fantastic news. It's absolutely central that we get this. I thank John Key for doing this," he said.
"People must be able to speak out - the people that want to - and [they] need to be able to do that unhindered."
Kokshoorn said the main points the inquiry needed to cover was why the explosion happened and how to prevent another one in the future.
The Prime Minister will travel to Greymouth with other ministers for a national memorial on Thursday.
FIRE AT MINE
Smoke and flames were last night billowing from the Pike River coalmine, with police admitting it is unrealistic to think the bodies of 29 miners will be recovered intact.
A fourth, more violent explosion rocked the mine yesterday shortly before 2pm, sparking a huge coal fire. The blast damaged a ventilation shaft, and flames could be seen coming through it from the air "like a Bunsen burner." Some vegetation near the shaft also caught fire and had to be put out.
Experts working to retrieve the bodies of the men, trapped since November 19, now have two options to get recovery teams into the mine.
A jet engine device – the Gorniczy Agregat Gasniczy (GAG) – is at the site ready to deploy. But experts need to determine if it can be used after last night's fire.
The mine could be temporarily sealed to starve the fire of oxygen.
Inspector Mark Harrison, who is heading the recovery operation, admitted it was less likely the bodies would now be removed intact.
"There's no time that could be put around this," he said. "We are gathering and assessing the information ... there's been a change in the environment within the mine and we need to know ... what that actually means."
Pike River Coal Chief executive Peter Whittall said families had been asking if they could get their men home by Christmas. A second explosion on Wednesday dashed any hopes the men would be found alive.
It could be some weeks before the bodies were returned, he said.
"I made the point then without being too blunt, Christmas is another `X' on the page as far as what the rescue teams are working towards. They've got to look at the actual time it takes them to do their job."
He added: "These last few days and the last couple of explosions have exacerbated the issue and probably pushed things out."
Whittall saw the smoke and flames when he flew over the mine yesterday afternoon and could smell coal smoke.
The GAG machine is his preferred option and would most likely be deployed in the evening. Sealing the mine (without using the GAG machine) would take longer, he said.
Using the GAG machine could take a number of days, New South Wales Mine Rescue Service general manager Paul Healey told Radio New Zealand.
The procedure would see gas or vapour pumped into the mine for at least three days before it is sealed and left to cool. The cooling of the mine could take some time, he said.
It is unclear if the fire is a "rubbish" coal fire – where coal dislodged by the explosions ignited – or "the worst-case scenario" of the entire coal seam catching alight. This would see the walls of the mine start to burn, Whittall said. "That's a lot harder to dig out or a lot harder to smother."
Key said yesterday that police may bring charges after investigations are complete.
Whittall said this was an inevitable possibility. "I understand that ... when the investigation comes out if someone's done something wrong then there should be consequences to that. I am not confident one way or the other."
Kokshoorn said the ventilation shaft was "sheared off" and blown to one side.
Families were "drained."
"They are subdued, they just want closure, they just want their loved ones back."
Lawrie Drew, father of Zen Drew, 21, said he was concerned his son would never be returned.
"Realistically we know no more than last Friday," Drew said. "All we know is they've missed quite a few opportunities to go in there and all we've got is everybody speculating."
COAL MINING FUTURE 'RESTS ON INQUIRY'
The future of underground coalmining in New Zealand rests on the findings of the royal commission of inquiry into the Pike River tragedy announced today, Key says.
Yesterday he said there were "very hard questions to be asked and answered".
"In the end, the future of Pike River and actually underground coalmining in New Zealand rests on this," Key told TVNZ's Q+A programme. "We can't put people into environments that are dangerous."
The royal commission would be carried out in addition to inquiries by the coroner's office, the Labour Department and the police.
There are four underground coalmines in New Zealand, involving 450 workers.
Greens co-leader Russel Norman said the inquiry should report in two parts, with the second looking at broader questions about the underground mining industry as a whole.
"There have been many questions raised about whether the regulatory framework is strong enough," Norman said.
The first part of the inquiry should focus on the specific cause of the explosion at Pike River to help provide closure for the victims' families.
"Part two would focus on the related issue of the broader safety and regulation of underground mining and could take longer to report back."
Norman said the royal commission should include a workers' representative.
Key said he could not speculate on the future of the Pike River mine.
"What I do know is it's claimed the lives of 29 men. They should be home with their families and they're not, and I owe it to those families to make sure that they get answers to those questions, and I'm determined to do that."
- JOHN HARTEVELT, AMY GLASS, KIRSTY JOHNSTON, ANDREA VANCE AND MICHAEL FOX