NEW ORLEANS (AP) - The Coast Guard says oil is now leaking from the damaged well that fed a massive rig that exploded this week off Louisiana's coast. Guard officials on Saturday estimated that as much as 1,000 barrels of oil is escaping each day from the well head on the ocean floor, increasing the threat to the Gulf's fragile ecosystem. As recently as Friday, the Coast Guard said no oil appeared to be leaking. Rear Adm. Mary Landry said on Saturday that the leak was a new discovery but could have begun when the rig sank on Thursday, two days after the initial explosion. BP PLC, which leased the rig and is taking the lead in the cleanup, says it's studying how to stop the leak. Eleven workers missing after the blast are presumed dead, and a search for them has been called off.