(Bloomberg) -- Rio Tinto Group has halted some work on an iron ore mine in Western Australia after an Indigenous rock shelter was damaged, three years after the company faced executive exits and public anger over the destruction of the Juukan Gorge caves. 

Operations were paused last month at the Nammuldi site 150 meters (roughly 490 feet) from the cave, after a large rock and scrub tree fell from an overhang above its entrance, Rio said in a statement. Sydney-listed shares in the world’s second-largest mining company fell as much as 2.9% on Friday, after a negative week for iron ore prices.

The latest incident in the Pilbara region comes after enormous backlash over the company’s actions at the Juukan Gorge ancient Aboriginal site in 2020, which culminated in the departure of both its chief executive officer and chairman. In recent years, Rio has also come under pressure to tackle wider issues of company culture, after accusations of sexual harassment, racism and bullying.

Read More: Rio Tinto’s Ruin of Australia’s ‘Stonehenge’ Sparks Reforms

“It’s not a good look for Rio,” said David Lennox, a resource analyst at Fat Prophets in Sydney, adding the company was supposed to have put measures in place to ensure key locations were protected. “There are hundreds of heritage sites that Australia’s resources sector needs to deal with, and unfortunately Rio has obliterated one and now appears to have damaged another.”

Rio’s Simon Trott, chief executive of the iron ore business, said the company had apologized to the traditional landowners, the Muntulgura Guruma people, and was working with them for guidance on how to proceed at the site.

The Wintawari Guruma Aboriginal Corporation, which represents the Eastern Guruma people in the Nammuldi area, has said it was disappointed by the news, but had yet to establish the extent of the damage. “It is pretty hard to discern from the photographs exactly what has happened. It sounds like Rio’s blast-mitigation measures have failed them,” corporation executive Aaron Rayner told The West Australian newspaper.

On its website, Rio describes the Greater Nammuldi Sustaining site as a key project to be delivered in the Pilbara over the next five years.

“Initial assessments taken by drone haven’t found structural damage to the rock shelter or impacts to any cultural materials,” Rio said in the statement.

A spokesperson for the company separately said there had been a blast at the mine site prior to the disturbance being detected at the cave. Blasting working at the site has been halted although some other operations are continuing, the spokesperson said.

The damage to the site comes three weeks before Australians vote in a referendum that could lead to the creation of an advisory body made up of Indigenous Australians, to give lawmakers feedback on policies affecting their people. The latest polls show the proposal is on track to be defeated. 

Read More: Australia’s Deepest Rifts Leave Indigenous Rights Vote in Peril

Rio’s shares closed 1.2% lower at A$114.57 in Sydney. The benchmark iron ore price has declined 1.6% this week.

(Updates share price in final paragraph)

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