GREYMOUTH, New Zealand, Nov 23, 2010 (AFP) - New Zealand rescuers on Tuesday released CCTV footage of an underground blast which trapped 29 miners last week, showing a powerful and sustained explosion.
The security video, which was shown to the miners' relatives and the media, showed white powder shooting out of the shaft's entrance for some 52 seconds before subsiding, as the camera shook.
Pike River Coal chief executive Peter Whittall said the video's release was intended to show the dangers of sending a rescue team into the mine after Friday's blast.
"It was a graphic representation of how dangerous it was to re-enter the mine," Whittall said.
Relatives have grown increasingly frustrated with rescue efforts, which have been stalled by a cocktail of toxic gases, making it impossible to send a search team into the mine.
On Tuesday, a converted army bomb-disposal robot broke down just 500 metres (yards) into the facility, while an exploratory bore-hole into the mine was delayed when drillers hit hard rock.
"There's a certain amount of anger right now," Grey District mayor Tony Kokshoorn told AFP earlier. "We've had a kick in the guts, the robot went in the tunnel, it got water in it and short-circuited, it's history.
"It's terrible. We're going into the fifth day and we're hearing this type of thing," he added.
