Four Chinese nationals were killed, and a Singaporean and Filipino were injured in an explosion on a super tanker off Malaysia's northern resort island of Penang, reports said today.

Northern Region marine police chief Zainul Abidin Hassan said the blast was believed to have occurred during welding work on the vessel late Sunday.

"The vessel was sailing from Singapore to India when the blast happened," Zainul Abidin was quoted as saying by the national Bernama news agency.

The 30,000-tonne Panama-registered ship MT Suva was lying about 215 nautical miles west of Penang, he added.

Marine police officials were unavailable for comment early Tuesday.

Carrying out repair work

The four dead were identified as Xu Xiad Ong, 39, Lui Yong Qian, 27, Kang Fan Lim, 27, and Xia Zhu Lan, 29.

The injured men, Filipino Jeselton Claver Adel, 25, and Singaporean Lim Puck Chow, 48, have been sent to hospital.

A Singaporean contract worker told Bernama that he boarded the ship with 11 other men to carry out the repair work when the blast occurred.

He said one of the dead was scalded by hot steam while two drowned after falling into a water tank and the fourth succumbed later to injuries sustained in a fall.