Both fatalities took place on Friday last week while a third accident on the same day at the Helensburgh Metropolitan Colliery has left a man with serious injuries.

James Adams jnr, 31, of Muswellbrook, was reportedly part of a crew working on underground development at Dartbrook, when he was trapped under rocks after a partial mine collapse at 1.50pm.

The Newcastle Herald reported that his father, James Adams snr, was with his son and three other crew members when the incident happened. Adams was freed but died soon after at the scene. The Newcastle Herald quoted an ambulance spokesman as saying the man was in cardiac arrest when ambulance crews from Muswellbrook arrived.

“At this stage the matter is in the hands of police and therefore we are unable to comment further, except to offer our deepest sympathies to the family and friends of the accident victim,” a

spokesperson for Anglo Coal said.

This was the third death in the mine's 12-year history.

The accident at Mount Thorley occurred after a giant dump truck got a flat tyre. Marathon Tyre employee Paul Strong was making the repair and was crushed to death while using a crane to repair the tyre on a 15-metre high Komatsu truck. The incident happened about 11pm on Friday.