Singapore - A Singapore shipyard explosion ripped off part of a barge and sent an Indian worker hurtling into the sea, news reports said Wednesday.

The man was able to swim ashore and was hospitalized with cuts on his back and head, the Manpower Ministry told The Straits Times.

He was working Tuesday aboard the 46-metre-long Orion 1505.

Sparks from welding were believed to have ignited flammable vapours, setting off the blast, the report said.

Four other workers including a safety supervisor were present at the time. They were not hurt, though one of the two cranes onboard the vessel was damaged and part of its stern blown off.

The spokesman said that investigations were underway. All work in the Pandan Road shipyard premises has been halted.

The explosion came nearly two months after safety officials urged shipyards to review safety procedures.

Eleven shipyard workers died and 286 were injured in the first six months of the year. Only three shipyard workers died on the job during the first six months of 2007.

Safety officials have been carrying out spot checks of the 89 shipyards in the city-state. (dpa)