MELBOURNE (Reuters) – Rio Tinto (RIO.AX) (RIO.L) apologised for the destruction of a sacred Aboriginal cave in Western Australia that showed evidence of continual habitation dating back 46,000 years, and said it would urgently review its plans for other sites in the area.

Rio Tinto blew up the cave last week in Juukan Gorge, about 1,075 km (667 miles) north of Perth, as part of an expansion programme in the Pilbara iron ore region, provoking a local outcry and calls for reform of heritage protection laws.

Explosives destroyed two ancient rock shelters, where artefacts discovered included 4,000-year-old plaited human hair with genetic links to the present day traditional owners, the Puutu Kunti Kurrama and Pinikura (PKKP) people.

“That site, for us, that’s where our ancestors were occupying their traditional land,” PKKP director Burchell Hayes told Australian Broadcasting Corp, adding that the community felt sorrow and sadness over the loss of heritage.

The mining giant, which had been granted state government approval in 2013 to damage or destroy the site under a legal framework that is currently under review, apologised on Sunday.

“We pay our respects to the Puutu Kunti Kurrama and Pinikura people, and we are sorry for the distress we have caused,” Iron Ore chief executive Chris Salisbury said in a statement.

The miner said that it had performed archaeological work in 2014 to preserve significant cultural heritage artefacts, recovering approximately 7,000 objects.

Rio said that it would work with traditional owners to look at its approach to preserving heritage.

“As a matter of urgency, we are reviewing the plans of all other sites in the Juukan Gorge area,” Salisbury said.

Federal Indigenous Affairs Minister Ken Wyatt last week flagged a need to strengthen the protection of indigenous sites, while his state counterpart said Western Australia was moving to fix out-of-date legislation.