A reinvestigation into the death of an Indonesian fisherman three years ago certified at the time to have been from natural causes has revealed allegations that he had been bullied by the Taiwanese captain and crew members before his death.

The Indonesian, named Supriyanto, died as the fishing vessel on which he had worked was on its way back to Donggang, Kaohsiung, southern Taiwan, in September 2015. The Pingtung District Prosecutors Office had ruled that it was a death from natural causes based on an autopsy report citing sepsis caused by an infected wound on his leg.

However, a former colleague of the deceased named Sukhirin returned from Indonesia to testify on Monday at the prosecutors office regarding a reinvestigation of the actual cause of death of his compatriot, The Liberty Times reported.

The initial autopsy report said Supriyanto’s leg wound had become fatal as it could not be treated properly because of limited resources on the seaborne vessel. The wound had reportedly been caused by a fall from height while the victim was hanging clothes.

Wang Mei-yu, a member of the Control Yuan – one of the five branches of the Taiwanese government – filed an application to the Ministry of Justice for a reinvestigation of the case, as there remained uncertainties and evidence that had been previously overlooked by investigators.

Wang pointed out that the interpreters in charge of the initial investigation could not understand Javanese and so failed to explain to the prosecutors office that the deceased had been physically abused by his colleagues.

The office also learned that there had been other vessels passing by the fishing boat, but the captain did not allow the sick Indonesian man to be taken away.

The witness Sukhirin argued that his colleague might have been saved if he had been allowed to return to land and receive medical treatment at a hospital.