The identity of a human skull and other bones discovered on a Nelson shoreline is a mystery.
They were found below the high tide mark on the coastal edge of the Nelson Airport walkway on Sunday by people who called the police.
"Interesting find for a Sunday aghhh freaky!" Mackenzie Rose posted on Facebook with a photo of the skull in the sand.
Detective Lex Bruning, of Nelson, confirmed it was a genuine find and believed the bones had been exposed by strong high tides.
He said police were working with Department of Conservation archaeologist Steve Bagley, and would refer the find to the coroner.
Mr Bagley, DOC technical adviser historic, said that besides the skull, a forearm, upper arm and shoulder blade bones were found. They were very weathered and he estimated they were between 50 and 150 years old. He could not tell the sex of the person or whether they were Maori or European.
From the teeth, he judged they were from an adult aged 30 or more.
He said there was no indication from the bones of injury or how the person had died.
Nothing was recorded of a burial site or urupa in the area, and he did not know how the bones had got there. He has returned them to the police.
Iwi liaison officer Archdeacon Harvey Ruru said he believed there needed to be some more work done, with a further look at the lay of the land.
Quite often after huge tides bones were discovered in coastal areas, he said.