Oil companies are evacuating some Gulf of Mexico oil rigs in advance of Tropical Storm Isaac.

For now the storm is close to the Dominican Republic and Haiti. But oil installations would be at risk if it heads to the Gulf of Mexico and reaches hurricane strength.

BP says it has begun evacuating all workers from its Thunder Horse platform in the eastern Gulf of Mexico, and will suspend oil and natural gas production there. It is also evacuating non-essential workers from offshore facilities in the central Gulf.

Apache Corp., the oil services company, says it is evacuating non-essential workers in the eastern Gulf of Mexico.