Auckland:
An explosion ripped through one of New Zealand's largest coal mines on Friday while dozens of workers were underground.
Five of them, dazed and slightly injured, stumbled to the surface hours later, and 27 were missing, officials said.
Police said that shortly before the blast the electricity went out in the mine, which may have caused ventilation problems.
That may have contributed to a buildup of gas underground.
Rescue teams were waiting for word that the mine was safe to enter.
The explosion was powerful enough to blow one driver off his machine deep in a tunnel, and a mine safety expert said gas was a possible cause of the blast, although police spokeswoman and the mine's operator stressed it was too early to say why it occurred.
Television footage showed blackened and singed trees and light smoke billowing from the top of a mountain where a 360-foot (110-metre) -long ventilation shaft emerges.
A nearby hut had been blown down, suggesting a powerful blast had shot up the shaft from deep in the mine.
Rescue teams and emergency workers rushed by helicopter and by road to the mine, located in remote and rugged mountains near the town of Atarau on New Zealand's South Island.
Local TV reported they were taking air samples in the ventilation shaft to check whether there was a buildup of poisonous or explosive gas and if it was safe to go in.
The condition of the missing miners was not clear, but the prospect that they could be alive but trapped recalls the dramatic saga of 33 Chilean mine workers who spent 69 days a half-mile (800 metres) deep in a collapsed gold and copper mine.
They were rescued last month in an event played out on international television that captivated the world.
Pike River chairman John Dow said each miner carried 30 minutes of oxygen supply - enough to reach oxygen stores in the mine that he said would allow them to survive for "several days."
The coal seam at the New Zealand mine is reached through a 1.4-mile (2.3-kilometre) horizontal tunnel that bores into the mountain toward the seam, which lies about 200 yards (metres) beneath the surface.
According to the company's website, the vertical ventilation shaft rises 354 feet (108 metres) from the tunnel to the surface.
Tony Kokshoorn, the mayor of nearby Greymouth, put the number of miners unaccounted for at up to 30.
Peter Whittall, chief executive of mine operator Pike River Coal Ltd., said 27 people were missing - 15 miners employed by the company and 12 local contractors.
Kokshoorn told National Radio that it was unclear at what depth the explosion happened but that it was clear that the blast was very large.
Whittall said five workers had walked out of the mine two to three hours after the blast: a pair that included the machine operator who was blown off his vehicle one mile (1.5 kilometres) into the access tunnel.
Three more came out later. One of the men had been able to make a call on his cell phone before reaching the surface, he said.
New Zealand Prime Minister John Key said the situation at the mine had the potential to be very serious.
Energy Minister Gerry Brownlee said the explosion happened at about 3:45 p.m. (0245 GMT, 9:45 p.m. EST) and the last contact with any of the miners was about half an hour later. They had not spoken to any of the missing miners during that time.
Two of the men who came to the surface were taken to a hospital for treatment of minor injuries.
"They're being interviewed and we're trying to determine ... the full extent of the incident," Whittall said.
It was not immediately clear if all of those underground were together or in separate groups.
Pike River has been operating since 2008, mining a seam with 58.5 (m) million tons of coal, the largest-known deposit of hard coking coal in New Zealand, according to its website.
Pike River says its coal preparation plant at the site is the largest and most modern in New Zealand and processes up to 1.5 (m) million tons of raw coal a year. It is country's largest single source of coal exports.
The mine's ventilation shaft was blocked by falling rocks in early 2009, delaying mining for months.
The mine is not far from the site of one of New Zealand's worst mining disasters - an underground explosion in the state-owned Strongman Mine on Jan. 19, 1967, that killed 19 workers.
Five of them, dazed and slightly injured, stumbled to the surface hours later, and 27 were missing, officials said.
Police said that shortly before the blast the electricity went out in the mine, which may have caused ventilation problems.
That may have contributed to a buildup of gas underground.
Rescue teams were waiting for word that the mine was safe to enter.
The explosion was powerful enough to blow one driver off his machine deep in a tunnel, and a mine safety expert said gas was a possible cause of the blast, although police spokeswoman and the mine's operator stressed it was too early to say why it occurred.
Television footage showed blackened and singed trees and light smoke billowing from the top of a mountain where a 360-foot (110-metre) -long ventilation shaft emerges.
A nearby hut had been blown down, suggesting a powerful blast had shot up the shaft from deep in the mine.
Rescue teams and emergency workers rushed by helicopter and by road to the mine, located in remote and rugged mountains near the town of Atarau on New Zealand's South Island.
Local TV reported they were taking air samples in the ventilation shaft to check whether there was a buildup of poisonous or explosive gas and if it was safe to go in.
The condition of the missing miners was not clear, but the prospect that they could be alive but trapped recalls the dramatic saga of 33 Chilean mine workers who spent 69 days a half-mile (800 metres) deep in a collapsed gold and copper mine.
They were rescued last month in an event played out on international television that captivated the world.
Pike River chairman John Dow said each miner carried 30 minutes of oxygen supply - enough to reach oxygen stores in the mine that he said would allow them to survive for "several days."
The coal seam at the New Zealand mine is reached through a 1.4-mile (2.3-kilometre) horizontal tunnel that bores into the mountain toward the seam, which lies about 200 yards (metres) beneath the surface.
According to the company's website, the vertical ventilation shaft rises 354 feet (108 metres) from the tunnel to the surface.
Tony Kokshoorn, the mayor of nearby Greymouth, put the number of miners unaccounted for at up to 30.
Peter Whittall, chief executive of mine operator Pike River Coal Ltd., said 27 people were missing - 15 miners employed by the company and 12 local contractors.
Kokshoorn told National Radio that it was unclear at what depth the explosion happened but that it was clear that the blast was very large.
Whittall said five workers had walked out of the mine two to three hours after the blast: a pair that included the machine operator who was blown off his vehicle one mile (1.5 kilometres) into the access tunnel.
Three more came out later. One of the men had been able to make a call on his cell phone before reaching the surface, he said.
New Zealand Prime Minister John Key said the situation at the mine had the potential to be very serious.
Energy Minister Gerry Brownlee said the explosion happened at about 3:45 p.m. (0245 GMT, 9:45 p.m. EST) and the last contact with any of the miners was about half an hour later. They had not spoken to any of the missing miners during that time.
Two of the men who came to the surface were taken to a hospital for treatment of minor injuries.
"They're being interviewed and we're trying to determine ... the full extent of the incident," Whittall said.
It was not immediately clear if all of those underground were together or in separate groups.
Pike River has been operating since 2008, mining a seam with 58.5 (m) million tons of coal, the largest-known deposit of hard coking coal in New Zealand, according to its website.
Pike River says its coal preparation plant at the site is the largest and most modern in New Zealand and processes up to 1.5 (m) million tons of raw coal a year. It is country's largest single source of coal exports.
The mine's ventilation shaft was blocked by falling rocks in early 2009, delaying mining for months.
The mine is not far from the site of one of New Zealand's worst mining disasters - an underground explosion in the state-owned Strongman Mine on Jan. 19, 1967, that killed 19 workers.
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