Six people on board a Taiwanese fishing vessel were forced to jump overboard on Tuesday morning after the vessel caught on fire about 19 nautical miles off the island.

The Taiwanese captain and his son, plus three Indonesian fishermen and a mainland Chinese crewman to jumped into the sea at about 11.20am on April 30.

Before they abandoned the ship, the skipper of the Hsin Chin Fa No.6 – a Su’ao township-registered vessel – alerted the Coast Guard Administration, saying they had a fire the engine and their location was 19 nautical miles off Nan’ao township in Yilan County, The Liberty Times reported.

A coastal patrol unit from Su’ao arrived at the scene quickly and picked up five of the six crew from the sea, while the remaining crew member – an Indonesian who sustained an injury to his leg – was airlifted to hospital by helicopter.

The five were brought back to the island and the Taiwanese captain and his son, surnamed Yu, were found to have sustained second-degree burns on their arms. They were immediately referred to a nearby hospital.

The crew members said the fire broke out very suddenly for unknown reasons and the entire vessel was soon engulfed by the blaze, forcing them to hurriedly abandon the ship.

Authorities said the vessel had undergone inspections and maintenance regularly, but officials would investigate to try to determine the actual cause of the blaze.