Indigenous community groups and advisors have confirmed Aboriginal man Eddie David, 39, has been imprisoned in a detention centre on the false claim of being in Australia illegally.

Mr David has been held in the Yongah Hill centre in Western Australia since Friday, despite proving intimate knowledge of Aboriginal culture and protocols to a cultural advisor.

“I’m not a refugee and I’m not an immigrant,” Mr David told the ABC.

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“I am Aboriginal, I am an Australian citizen, born and bred of this land.

Mr David was taken into custody after Centrelink officials claimed his passport was fake. He claims to have been born in the Torres Strait and to have applied for his passport in March with the help of the Aboriginal Land and Sea Council.

Two experts as well as the man’s employer confirmed to the ABC their belief in Mr David’s Aboriginality.

The Department of Immigration and Border Patrol has denied the claim.

“The department detained an individual claiming to be an Australian citizen, following a thorough investigation by which the department was fully satisfied that he is an unlawful non-citizen,” the department said in a statement.

Fellow detainees have reportedly expressed sympathy for Mr David’s plight.

“They’re shocked that there’s an Aboriginal Australian in a detention centre,” he said.

“They say, ‘This is your land, you should be out there, not in here’.

“It’s a mistaken identity.”