A well of Royal Dutch Shell, a global oil and gas company, spilled about 13,000 gallons of oil and drilling fluids into the Gulf of Mexico on Sunday, U.S. media reported on Monday.

The area where the well was being drilled is about 32 kilometers from the site of last year's BP oil spill, and Shell is working in water more than 2,133 meters deep, according to the daily newspaper The Press-Register.

The spill was composed of 7,560 gallons of oil and 5,829 gallons of synthetic drilling fluid, the paper said, citing the Shell report with the National Response Center.

The spill was reported Sunday by Transocean's Deepwater Nautilus rig, which was drilling the well at Shell's Appomattox discovery.

"Shell can confirm it has a loss of drilling fluid from a booster line, which provides additional drilling fluids and is separate from the wellbore itself," Shell spokesman Kelly op de Weegh said in a statement Monday afternoon.

"The leak was isolated, stopped and remedial action has been approved... which includes temporarily abandoning the well, pulling the riser and making appropriate repairs," Weegh said.

The U.S. Bureau of Ocean Energy Management, Regulation, and Enforcement sent inspectors to the scene on Monday, according to media reports.

The U.S. Coast Guard was trying to determine what material was leaked, said Coast Guard spokesman Steve Lehmann, adding that overflight from New Orleans found "a very light sheen in the vicinity" of the site.

BP's Macondo well ruptured after the Deepwater Horizon oil rig exploded and sank in April last year, spewing up to 4.9 million barrels of oil into the Gulf for nearly three months, making it the world's worst marine oil spill.

A government report released in September blamed BP and other companies for a series of failures that helped lead to the spill.