Greymouth: New Zealand Prime Minister John Key said on Thursday he wanted answers on what went "terribly wrong" in a colliery blast that killed 29 men in the nation`s worst mining disaster for almost a century.
He also warned it could take "months" to recover the bodies of the workers who died underground in one of the country`s worst mining disasters, as the grieving mining community pleaded for the return of their loved ones.
As flags across New Zealand flew at half-mast, Key said the nation was struggling to understand the tragedy at the Pike River colliery, where miners trapped by an explosion last Friday were confirmed dead after a second blast on Wednesday.
"We need answers to what happened at Pike River. Clearly something`s gone terribly wrong and it`s now claimed the lives of 29 people," said Key, who has travelled to Greymouth on New Zealand`s South Island to be with the families.
"The nation is grieving and mourning alongside them," he said.
"It`s only right and natural and fair that the family members would want to have the bodies recovered so that they can have some closure."
However, a lethal cocktail of volatile gases remained in the mine and Key said this would delay recovery attempts.
"That (recovery) has to occur in a way that is safe to those that would undertake that mission," he told reporters. Previous international experience had shown the operation could take "quite some months", he said.
As messages of condolence poured in from around the world, Key praised the rescue efforts, which some relatives of the miners have criticised after the gas threat stopped emergency workers from going underground.
"It wasn`t for the want of trying, or the willingness, or the courage or the bravery of those that would have gone in to undertake the rescue -- it was just the reality of the situation," he said.
"A mine in this condition is a highly volatile environment, liable to explode at any time without any notice."
Authorities have launched at least four inquiries into the disaster, whose victims ranged from a 17-year-old on his first shift to a 62-year-old veteran, and included two Australians, two Britons and a South African.
"This is a mine that`s claimed the lives of 29 men and they (the families) are entitled to honest answers about what went wrong, what lessons we can learn," Key said.
Mine owner Pike River Coal said it would cooperate fully and was holding its own investigation into the disaster at the colliery, a new facility that sent its first shipment of hard coking coal for steelmaking to India only this year.
US Secretary of State Hillary Clinton joined Australia`s Prime Minister, Britain`s Queen Elizabeth II -- who is also the head of state of New Zealand -- and other dignitaries in expressing their "heartfelt condolences".
New Zealand has lost "29 brave and hard-working men who will be mourned around the world", Hillary said as the queen said she was "deeply saddened" by the deaths.
"My heart goes out to the families and friends of these 29 brave miners and to all who have been touched by this national disaster," she said in a message to Key released by Buckingham Palace.
Grey District Mayor Tony Kokshoorn, who declared the incident the "darkest hour" of the South Island`s rugged West Coast region, said the focus has turned to the grim task of recovering the bodies for the grieving families.
"They won`t feel closure until they`re (with) their loved ones," he told TVNZ.
New Zealand`s other major mining company, Solid Energy, has suspended underground operations at its Spring Creek mine near Pike River and its Huntly mine in the North Island as a mark of respect, chief executive Don Elder said.
A number of specialist mine rescue staff from Spring Creek and Huntly were involved in the Pike River rescue operation.