It’s unclear what caused a fishing vessel fishing to sink in the Southern Ocean this morning.

Of the Oyang 70’s crew, 45 of 51 have been rescued. The bodies of three others, all Indonesian nationals, have also been recovered.

Three people remain unaccounted for including the ship’s master.

WeatherWatch.co.nz says conditions in the Southern Ocean would be cold and windy with a large low in the area creating strong cold southerlies.

The water temperature is around 8 degrees.

Hypothermia would kick in instantly in conditions that cold says WeatherWatch.co.nz.  If crew managed to get their survival suits on they could last hours.

Rescue Coordination Centre spokesperson Sophie Hazelhurst says an Air Force Orion is at the scene and six ships are helping with the search and rescue operation.

She says they understand the vessel was in the process of hauling in its fish catch when it capsized.

– WeatherWatch.co.nz with NewstalkZB.co.nz