A fuel line on a tanker loading bunker oil from a barge ruptured early Friday morning, spilling a mile-long sheen of oil into the San Francisco Bay in the U.S. state of California, local media reported. The accident occurred when the tanker Dubai Star and the barge were anchored a few miles south of the San Francisco-Oakland Bay Bridge, the San Francisco Chronicle reported on its website, quoting Coast Guard officers. The Marine Spill Response Corp., a nonprofit oil-spill removal organization, has sent three major oil cleanup vessels to the scene and booms have been placed around the Dubai Star to contain the oil. San Francisco Mayor Gavin Newsom convened a half-hour conference call with the Coast Guard and other departments Friday morning and was told that fewer than 100 gallons had spilled into the bay, said Nathan Ballard, a spokesman for the mayor. A large patch of spilled oil has drifted south with the tide, but so far there were no reports of oil washing up on shore. Officials said it is too early to tell what the effect might be on wildlife. 