BP investigates new oil sheen in Gulf

British oil giant BP said Thursday it and other companies were asked by the U.S. to investigate an oil sheen spotted in the Gulf of Mexico by the U.S. Coast Guard last week, but said the sheen had nothing to do with its operations. The London-based company said in a statement it and other oil and gas companies were asked by the Coast Guard to investigate the cause of the sheen in the Green Canyon area of the Gulf of Mexico. BP has two abandoned exploration wells in that area. BP did not disclose the names of the other companies involved in the investigation. BP had sent an unmanned submarine to the area over the weekend to investigate the source of the sheen, and concluded that the sheen had nothing to do with BP's operations, a BP spokesman said. BP's Macondo well ruptured after an oil rig exploded and sank on April 20 last year, spewing up to 4.9 million barrels of oil into the Gulf of Mexico for nearly three months in the world's worst marine oil spill. BP is the largest leaseholder in the Gulf of Mexico.