A Bangladeshi asylum seeker has died from heart failure on Nauru.

The 26-year-old detainee at the Nauru detention centre took himself to hospital on Monday complaining of chest pains but died on Wednesday after a series of cardiac arrests.

The Department of Immigration said a helicopter was dispatched to the island but the man’s condition prevented his transfer to Australia.

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Refugee advocate Ian Rintoul said in a statement the refugee had taken an overdose of tablets including Panadol.

He called for a proper investigation.

Australian Greens senator Sarah Hanson-Young said the death could be the second suicide on Nauru in a fortnight.

“The investigation cannot be left to the Nauru Police or (Immigration Minister) Peter Dutton’s department, both of whom clearly cannot be trusted,” she said.