The heartbreak still is being felt in the Cobar community following the death of 2 locals and serious injury to another in Endeavour's tragic mine explosion .

On November 25 the NSW Resources Regulator issued an investigation information release following the deaths of two workers at Endeavour Mine in Cobar, NSW on Tuesday 28 October 2025.

The report says the Regulator has a way to go but initial investigation gives progress for families, mine owners and community.

"Three workers were in the underground workings at the mine about 3.30 am, preparing a ballistic disc to clear a hang-up in a drawpoint." the report says.

"While the 3 workers were preparing the ballistic disc underground, it unintentionally detonated resulting in two workers suffering fatal injuries, while a third worker was seriously injured."

The new investigation confirms that inspectors are examining the mine’s procedures for handling and preparing ballistic discs and electric instantaneous detonator assemblies, including the instructions, training and supervision provided to workers involved in the task.

Investigators are also assessing whether radio frequency interference from underground communication systems – such as two-way radios, mobile phones, smart watches and signal amplifiers — may have played a role.

Additionally, the regulator will review risk assessments, safe-work instructions, and the guidance issued by designers and manufacturers of the explosive devices.

A technical assessment of the ballistic disc and detonator is underway to verify compliance with manufacturer specifications.

The use of electric instantaneous detonators to initiate ballistic discs is also under scrutiny.

The Resources Regulator has commenced an investigation to determine the cause and circumstances of the incident and will issue a report at the end of the investigation.

Polymetals Resource says they are continuing to work with the regulator.

"We will forever remember Patrick “Ambrose” McMullen and Holly Clarke who lost their lives on October 2025," a spokesperson said.

"The safety and well being of our team will always be our number one priority.

"We are committed to finding out how this accident happened. Investigations are ongoing.’’