The driver of the 2km-long BHP-operated train stepped out of the locomotive early on Monday to inspect an issue with one of its 268 wagons and it took off without him.
It hurtled along the company’s Newman to Port Hedland line in the remote Pilbara region for about 50 minutes until it was deliberately derailed at a set of points near Turner, about 120km south of the port town.
The action was taken by a remote control centre more than 1,500km away in Perth.
No one was injured.
The Australian Transport Safety Bureau said damage to the train was substantial and it is estimated about 1.5km of track was damaged.
“We are working with the appropriate authorities to investigate the situation,” a BHP spokeswoman said in a statement. “Recovery operations are under way.”
BHP’s WA rail operations are expected to resume in about a week.
The company did not report the matter to the Australian stock exchange as it is not expected to have a material impact on finances.
BHP has large iron ore stockpiles at port, so it is unlikely any scheduled shipments will be missed.
The ATSB is investigating the incident and expects its report will be complete in the second quarter of 2019.
The WA premier, Mark McGowan, said he had not been briefed on what happened but it would have been very concerning for everyone involved.
“Extraordinary measures obviously had to be used,” he told reporters on Tuesday. “I’m sure that there will be a full review undertaken by BHP and I’ll consult about what role the state might have in that.”
The transport minister, Rita Saffioti, said the National Rail Safety Regulator had been informed and was investigating.
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