An explosion ripped through an oil rig in the Gulf of Mex-ico yesterday forcing 13 people into the water, one of whom was injured, the US Coast Guard said.

The rig was still ablaze and the blast raised fresh pollution fears as the region struggles to recover from the largest ever maritime oil spill, caused by a similar explosion a few hundred kilometers to the east.

Helicopters rushed to the scene of the latest blast to fish out workers who apparently jumped into the sea to save themselves. Officials said it was too early to know about potential pollution.

“All 13 are accounted for and they are all wearing some sort of an immersion suit that protects them from the water,” Coast Guard chief petty officer John Edwards told MSNBC.

Nine helicopters had been dispatched to the rig 130 kilometres south of Vermilion Bay in Louisiana, the spokesman said, adding the extent of any injuries suffered by the workers was not immediately clear.