5:45 pm: This post has been updated.

The Coast Guard reported today that a mile-long oil sheen is spreading in the Gulf after an offshore oil rig exploded and caught fire earlier today, about 200 miles west of BP’s ruptured Deepwater Horizon well.

The rig is owned by a company called Mariner Energy, which has been involved in at least 13 accidents in the Gulf of Mexico since 2006, “including a blowout and four fires,” reported the Houston Chronicle.

No one was killed in this latest incident and the 13 workers aboard the rig were rescued. The platform, however, is still ablaze, and Mariner Energy’s early report of no leak has been cast into doubt. (The company also said in its press release that no injuries have been reported, although one person was reported injured.)

"Mariner has notified and is working with regulatory authorities in response to this incident. The cause is not known, and an investigation will be undertaken," the company said in a statement.

In April, Apache Corp., another petroleum company, announced it was acquiring Mariner, but according to the Associated Press, that deal is pending. More from the AP:

Apache spokesman Bob Dye said the platform is in shallow water. Responding to any oil spill in shallow water would be much easier than in deep water, where crews depend on remote-operated vehicles access equipment on the sea floor.

ThinkProgress points out that both Mariner Energy and Apache Corp. were at a rally just yesterday to protest the Obama administration’s temporary moratorium on offshore drilling. ThinkProgress pulled the following from the Financial Times:

Companies ranging from Chevron to Apache bussed in up to 5,000 employees to the Houston convention centre to underline to Washington the industry’s contribution to the country. ...

“I have been in the oil and gas industry for 40 years, and this administration is trying to break us,” said Barbara Dianne Hagood, senior landman for Mariner Energy, a small company. “The moratorium they imposed is going to be a financial disaster for the gulf coast, gulf coast employees and gulf coast residents.”

Mariner is one of the smaller players in the Gulf: The rig that exploded produced, on average, about 1,400 barrels of oil a day during the last week of August, the company said. By comparison, some of BP's smaller wells produce more than 60,000 barrels a day.

While not nearly on the scale of the BP’s Deepwater Horizon disaster, the latest accident still probably doesn’t help bolster the industry’s argument that the risks of offshore drilling are overblown.

Update: The Coast Guard has backed off its earlier report of an oil sheen, and is now reporting that there are no signs of a spill.

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