Indonesian police said Friday that they had foiled a bid to smuggle the bodies of three crew who died on a Chinese fishing vessel back to the Southeast Asian nation.

The discovery marked the latest in a string of recent cases where Indonesians died or suffered abuse on the high seas, including one man who was allegedly killed by his Chinese supervisor and then stuffed inside a freezer.

Jakarta and Beijing earlier pledged to probe the incidents, which anti-trafficking experts say highlight a fishing industry riddled with forced labour and exploited workers who face non-payment, overwork, violence and even death.

On Friday, police in Indonesia's Riau islands near Singapore said they had arrested half a dozen suspects after intercepting a wooden boat carrying the crew who had died on the vessel Fu Yuan Yu 829 earlier this month, police said. 

An autopsy was being conducted on Friday, they added.

In a "new trick" to avoid detection, the Chinese ship fled after the bodies were moved to the smaller boat which was nabbed on Thursday, according to authorities.

The move was aimed at returning the dead crew to Indonesia under the radar, they added.

Two of the six arrested -- executives at a firm that recruits Indonesian crew -- face human trafficking charges which can carry a life sentence, said Arie Dharmanto, chief criminal investigator for the Riau islands police.

Last month, authorities intercepted two Chinese vessels near Singapore and found the body of Indonesian crew Hasan Apriadi inside a freezer on one of the ships.

Police charged a Chinese supervisor with allegedly torturing Apriadi to death. A half dozen Indonesian recruiters were also arrested in the case.

In June, two Indonesian crew jumped off a Chinese boat to escape what they described as abuse and horrific conditions, sparking a string of arrests.

A month earlier, three dead Indonesian crew members were thrown off a Chinese-flagged vessel into the sea.