A fifth robot has failed inside the Pike River Coal mine.
Two army robots and two mine rescue robots hired from the West Australian Water Corporation have already been abandoned inside the mine after failing part-way into the two-kilometre entry shaft.
Twenty-nine men were killed in explosions in the mine in November and there is growing frustration among the men's families that no one has gone in since.
One of the mine company's receivers, John Fisk, says the latest attempt with a robot on Friday also failed.
