NZ Mine Explosion: "The Pike 29"

Emergency services will today assess whether it's safe enough to begin a rescue mission for 29 miners trapped in the Pike River Coal mine, 46km NE of Greymouth, Sth.Island yesterday afternoon.
There are 16 mine employees and 13 contractors unaccounted for, following the explosion at the isolated underground mine. [UPDATE: two Australians, two Scots and a Sth.African are among the 29.]
An electrician checking a power outage went into the mine and found a driver who had been blown off his machine about 1500m inside the shaft. The two were able to clamber to safety through an escape route, but have no idea of the whereabouts of the others.
Last night the official word was that there was no evidence of any fatalities, but all underground communication was severed by the explosion. Amid concerns about ventilation, PRC says everyone inside has a self-rescue device which generates oxygen from their own breath. There are also refuges at regular intervals where people can get fresh supplies.
An explosion of this size certainly doesn't auger well but thoughts automatically return to the successful rescue of the Chilean miners last month - they were trapped 700m down. The NZ workers are about 120m beneath the surface, but about 2.5km into the mine. The Pike River Coal mine is the country's largest underground coalmine.
[UPDATE: Australia is sending a technical expert and six mine rescue experts to assist.]
[UPDATE, 8am Mon: drilling continues on a bore hole to gain air samples, to determine whether air is safe enough to send rescuers into the mine. One has to wonder, if it's too risky for fully-equipped rescue teams to enter, what hope is there for the "Pike 29"? Family frustration is growing over the pace of efforts.]
[UPDATE, 6pm Mon: mine officials bracing for loss of life...]
[UPDATE, 6am Tue: scientist hypothesises about a fireball in the mine...]
[UPDATE, 1pm Tue: a military robot, sent down the mine for reconnaissance, malfunctions...because it was not waterproof!
W - T - F???!!! This mission is rapidly degrading into Greek tragedy! Robots are on the way from Oz and USA.]
[UPDATE, 8pm Tue: a camera inserted into a place of safety shows no sign of activity...]
[UPDATE, 5pm Wed: second explosion: authorities now say there's "no chance of survivors"]
PS: 25 Nov.2010 - Flags flew at half-mast across NZ, as the Prime minister called today a national day of mourning.
[Just last Monday 15th at its AGM, Pike River Coal revised its targets downwards, advising shareholders of more realistic timeframes and production scenarios. After the explosion, the Australian-listed shares of PRC were put on a 'trading halt' but not before shares had slumped by 10c or 14%, to close at 61c. Trading resumes Tuesday or following an announcement from the company. The NZ share market had already closed at the time of the explosion.]