An oil rig exploded about 90 miles south of Vermilion Bay, Louisiana, Thursday, sending all 13 of its crew members into the water. In a statement, the U.S. Coast Guard said it responded to reports of the explosion at about 10 a.m. this morning

As helicopters flew in from New Orleans and Houston, crew members clung to emergency flotation devices. All have been rescued; one injury was reported.

White House spokesperson Robert Gibbs said this morning during a press briefing that the government is ready to deploy a response to the rig, if needed.

The shallow water rig was not producing oil at the time, and no spill of oil into the water has been reported. UPDATE: The Associated Press is reporting that a one-mile-long oil sheen was spotted near the platform. It is located about 200 miles west of BP's Macondo well, which exploded during production in April, killing 11 workers and causing the largest recorded maritime oil spill.

Houston-based Mariner Energy owns the Vermilion Oil Platform 380 rig. The company's shares dropped 5 percent on news of the explosion.

"The cause is not known, and an investigation will be undertaken," Mariner Energy said in a statement.

During the last week of August 2010, production from this rig averaged approximately 9.2 million cubic feet of natural gas per day and 1,400 barrels of oil and condensate, the company said.

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