Fortescue Metals Group Ltd. said it had been subject to a cyber attack that resulted in “the disclosure of a small portion of data from our networks.”

The world’s fourth-largest iron ore exporter described the attack as “a low impact cyber incident” that occurred on May 28. The information disclosed “was not confidential in nature,” the Perth-based company said in an emailed response to inquiries.

“We notified the Australian Cyber Security Centre of the incident, and our internal investigation and remediation actions are now complete,” Fortescue said.

The Australian newspaper reported on Tuesday that Russian ransonware gang C10p — also known as “Clop” — had claimed via a blog on the dark web that it had stolen customer data from Fortescue in a “financially motivated” attack. The gang hadn’t released the data and was seeking a ransom from Fortescue, the paper said, without saying when the information was posted on the blog.

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