Search operations are going on to locate seven fishermen who were reported missing after their fishing boat capsized in a tornado on Monday night in the sea off the southern province of Binh Thuan.

The map shows the spot where the fishing boat was hit by the tornado on the sea in Binh Thuan Province.

On Monday night, fisherman Vo Van Hung, 32, from southern Ba Ria-Vung Tau province's Xuyen Moc District, and seven other fishermen on the boat, BV 95568-TS, were on their way back home after spending 20 days at sea when a tornado struck the area they were fishing in. It reportedly flooded the boat.

Vo Hoai Vui, Hung's younger brother, who survived the mishap, said he was still in shock following the incident in which his brother and other fishermen are still to be traced.

That night, as the other fishermen slept and Hung, the captain of the boat, was steering it back to shore, the tornado struck, tossing the boat around.

Vui said that he and another fisherman managed to escape through the hatch at the rear of the boat before it capsized.

The two survivors managed to stay afloat by calling out to each other during the night, Vui said.

He managed to stay awake and survived, but the other man died of exhaustion.

Pham Hien, director of the Maritime Search and Rescue Co-ordination Centre in Ba Ria-Vung Tau City, said that the centre has dispatched a ship to the scene and co-ordinated with the coast guards and border guards in Binh Thuan province to search for those missing.