Australian maritime authorities have identified a large area in the Indian Ocean where they will focus the search for a capsized Chinese fishing vessel, which reportedly sank on Tuesday with 39 crew members.

A spokesperson for the Australian Maritime Safety Authority (AMSA) told the Chinese state-run Xinhua news agency on Thursday that based on drift modelling, a remote 12,000 square km zone has been identified to search for the vessel.

A Chinese deep-sea fishing vessel capsized on Tuesday in the central Indian Ocean, which has so far left 39 people on board missing, including 17 Chinese mariners, 17 Indonesian mariners and five Philippine mariners.

Chinese Foreign Ministry spokesman Wang Wenbin told media here on Wednesday that the Chinese and foreign vessels have arrived at relevant waters to conduct a search and rescue operation after the fishing vessel “Lupeng Yuanyu 028” capsized.

More help is on the way. "We will continue to work together with relevant sides to do everything possible to find those who have gone missing," he said.

"We would like to thank the Australian maritime search and rescue department for sending an aircraft and coordinating foreign vessels passing by to help with the search and rescue efforts.

We hope countries nearby will continue to join our search and rescue efforts. We will not give up as long as there is still hope for saving lives,” he said.

An AMSA spokesperson said that they continued to coordinate a multinational search effort after a distress beacon signal was received by AMSA from the fishing vessel at about 5:30 am (AEST) on the morning of May 16.

AMSA requested assistance from the Australian Defence Force (ADF). An ADF P-8A Poseidon aircraft was tasked with assisting with the long-range search. The ADF aircraft will rejoin the search on Thursday after overnighting in the Maldives, the Xinhua report said. A private charter aircraft from Perth, with State Emergency Service (SES) observers on board, also assisted with the search on Wednesday and will rejoin the search on Thursday.

"A number of merchant ships and other vessels have been assisting with the search and will continue to do so today. AMSA would like to thank these vessels and their crews for their invaluable assistance," the spokesperson said on Thursday.

"Australia has been liaising with the Chinese Maritime Rescue Coordination Centre (MRCC), with three Chinese naval ships continuing the search in the area today," the spokesperson said.

Officials said weather conditions have calmed significantly since Tuesday. Four vessels, including two foreign ships, are undertaking on-site search work.

AMSA said it is also working with the China Meteorological Administration to predict the drift of the missing crew, and it is enhancing its coordination with search and rescue agencies in Australia, the Maldives and Sri Lanka.

Official media reported the transport ministry also coordinated with maritime search and rescue agencies of Australia, Maldives and Sri Lanka to send additional forces to carry out search and rescue and made no mention of whether any assistance was sought from India as the Indian Navy has a sizeable presence in the Indian Ocean.

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