Western Australia's safety regulator has been alerted to an incident at billionaire Andrew "Twiggy" Forrest's mine site party celebrating his company's success.
Hundreds of business leaders and mine workers flew to Fortescue Metals Group's Solomon mine site in the Pilbara for the gala bash on Saturday night.
They were toasting FMG's 20-year anniversary, which included rocking out to Australian music great Jimmy Barnes and a plentiful supply of seafood and alcohol.
Photos from the event show Dr Forrest, Australia's richest man, hugging the performer on a massive stage built in the remote desert site before a cheering crowd.
A spokeswoman for the company, which is the fourth-largest iron ore producer in the world, said an incident at the party was reported to the Department of Mines, Industry, Regulation and Safety.
Deputy WorkSafe commissioner Sally North said it had not received complaints about the event and was conducting routine inquiries to ensure FMG had appropriate safety systems given the size of the event.
"FMG did not have to notify WorkSafe of the celebrations and the company is responsible for the health and safety of all people who attend any of its mine sites," Ms North said.
"WorkSafe Mines Safety did not visit the Solomon mine site immediately prior to the event but will continue to conduct its routine compliance inspections."
FMG said the party was held using the highest health and safety standards and a risk management plan ensured the event met legislative requirements.
This included adhering to the responsible service of alcohol policy and staffing the event with experienced security personnel.
"Fortescue has a long history of holding events to celebrate milestones for its Fortescue family," the spokeswoman said.
"Our top priority is the health, safety and well-being of our team members, contractors and communities."
Fortescue said the event was held in a designated area separate from its mining operations and staff working at the site did not attend.
The mining giant is dealing with yet another executive loss, days after the shock exit of chief executive Fiona Hick.
In a brief ASX statement on Thursday, Fortescue announced the departure of Christine Morris as chief financial officer.
The company did not disclose the reason for her departure, having only started in the role in July.
Apple Paget has been appointed acting CFO.
A number of executives and board members have left the company in the past 12 months across its mining and green energy operations.