Australians among trapped miners

Gas fears: Rescue teams are waiting for clearance to enter the mine. (ABC: file photo)

At least two Australians are among the 29 workers missing after an underground explosion in a New Zealand coal mine.

Confusion surrounds when a rescue bid may be made, after Grey District mayor Tony Kokshoorn earlier said rescue staff had been given the green light to enter the mine.

Cr Kokshoorn told the New Zealand Herald that results from three air samples showed gas at the mine was not explosive, but Pike River chairman John Dow said no test results of the air from the mine had come back today.

Mr Dow said the rescue effort would not get underway for hours because the company is uncertain of when they would be able to gather suitable air quality samples.

Two miners managed to get out of the mine on the country's South Island yesterday, but so far, there is no sign of the other men.