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Rio Tinto will cut the bonuses of three senior executives by a combined £3.8 million ($5 million) after the company blew up a 46,000-year old sacred indigenous site in Australia to expand an iron ore mine.

In a report published Monday into the destruction of the Juukan Gorge caves in Western Australia in May, the company said that it failed to meet some of its own standards “in relation to the responsible management and protection of cultural heritage.”

But Rio Tinto stopped short of firing any executives, drawing criticism from investor groups who accused the company of failing to take full responsibility for the demolition of the caves, which had significant archeological value and deep cultural meaning for aboriginal people.

The site featured two cave systems that contained artifacts indicating tens of thousands of years of continuous human occupation. In a report given to Rio Tinto (RIO) before the planned expansion of its Brockman 4 mine, a leading Australian archeologist said the archaeological significance of the shelters “cannot be overstated.”

Demolition went ahead on May 24 despite a seven-year battle by the local custodians of the land, the Puutu Kunti Kurrama and Pinikura people, to protect the site. Rio Tinto apologized in June.

“It is clear that no single individual or error was responsible for the destruction of the Juukan rockshelters, but there were numerous missed opportunities over almost a decade and the company failed to uphold one of Rio Tinto’s core values — respect for local communities and for their heritage,” Chairman Simon Thompson said in a statement on Monday.

“We will implement important new measures and governance to ensure we do not repeat what happened,” he added.

Rio Tinto said it will withhold performance bonuses from CEO Jean-Sébastien Jacques, the head of its iron ore business Chris Salisbury, and group executive for corporate relations, Simon Niven.

In addition to having his £1.7 million ($2.2 million) bonus withdrawn this year, Jacques will have awards due to vest in 2021 reduced by £1 million ($1.3 million). The CEO earned £5.8 million ($7.6 million) in 2019 including salary, benefits, a bonus and stock awards, according to Rio Tinto’s latest annual report.

Investor groups in Australia said the company’s actions do not go far enough.

“The report from the Rio Tinto board review does not deliver any meaningful accountability for the destruction of some of the most significant cultural sites in Australia,” Louise Davidson, the CEO of the Australian Council of Superannuation Investors, said in a statement. The body represents institutional investors.

Not only did the destruction of the caves result in a “devastating cultural loss,” but it is of significant concern to investors because it puts at risk Rio Tinto’s “social licence to operate,” Davidson added.

“This is a devastating outcome for the Puutu Kunti Kurrama and Pinikura people, and a massive loss to the heritage of all Australians,” said Simon O’Connor, the CEO of the Responsible Investment Association Australasia. “The information revealed to date has exposed large failings in the internal processes to deliver upon the company’s own commitments to protecting indigenous heritage,” he added.

According to Rio Tinto, “material new information” that came to light after legal approvals for the mine were obtained in 2013 should have led it to reconsider its expansion plans.

For example, in a 2014 report, Australian archaeologist Michael Slack identified the shelters as “one of the most archaeologically significant sites in Australia.”

These findings were amplified in a final report provided to Rio Tinto four years later, in which Slack said the site “has the amazing potential to radically change our understanding of the earliest human behaviour in Australia… The significance of this cannot be overstated.”

The Puutu Kunti Kurrama and Pinikura Aboriginal Corporation did not immediately respond to a request for comment.