The incident took place early Monday afternoon, according to a spokeswoman.
“No one was injured as a result of the incident,” Illawarra Coal said.
“All employees were evacuated and accounted for, and a full investigation is underway.”
No other details were provided, including where the roof fall took place underground, the size of it, and how long operations were disrupted for.
In late June a worker injured his foot at the underground mine, while in February 2012, a miner lost three fingers after his hand got wedged between the canopy of the coal tram he was driving and a rib.