Authorities are investigating whether culturally significant Aboriginal rock carvings on Tasmania's rugged northwest coast have been deliberately damaged.
The state's Parks and Wildlife Service received a report on Monday that petroglyphs at Sundown Point had "changed".
Officers from the Natural Resources and Environment Department are examining if part of the site had been dislodged by tides or removed.
Aboriginal Land Council of Tasmania chair Michael Mansell said the carvings, which are mostly covered at high tide, were made in harder rock than others in the region.
"Because of the type of rock into which the signs were carved. It is such a hard rock ... there is no way the sea is going to push it off," he said.
"We suspect someone has gone down there and damaged them."
Petroglyphs at Sundown Point, in the Arthur-Pieman Conservation Area, have been defaced and stolen in the past.
In 1999 they were spray painted by vandals. The year prior, a section of rock carvings was cut off and taken. It has never been recovered.
"The most precious, irreplaceable carvings in Tasmania are all on the west coast," Mr Mansell said.
"Most people appreciate the value of these things, but not everybody."
Anyone with information has been asked to contact Tasmania's Parks and Wildlife Service.
The investigation comes amid the near culmination of a decades-long fight to return 14,000-year-old petroglyphs from the Tasmanian Museum and Art Gallery (TMAG) to their original location at Preminghana.
The carvings were removed in the 1960s and put on display at the museum. Their return to the northwest coast is expected in coming months.
TMAG and the Royal Society of Tasmania made a formal apology to the island's Indigenous people last year to acknowledge "200 years of morally wrong practices".
"We acknowledge the Royal Society exhumed and purchased remains of Aboriginal people for scientific study, some of which were sent out of the country," Royal Society president Mary Koolhof said.
Australian Associated Press
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