The California oil pipeline has essentially been pulled like a bowstring. (File)Los Angeles:
A fractured pipeline spewing crude oil off the coast of California could have been leaking for a year, US investigators said Friday.
Tens of thousands of gallons of oil are feared to have leeched into waters that are home to whales, dolphins and otters since a leak was discovered last weekend.
Stretches of prime surfing coastline have been shuttered as clean-up crews raced to prevent the spoiling of beaches and rescue animals caught up in the slick.
US news outlets reported that a ship's anchor could have been responsible for dragging the pipeline along the seabed and splitting it open.
But Coast Guard officials investigating the incident said Friday the rupture might not be new, and could have happened as long as a year ago.
Captain Jason Neubauer said multiple ships' anchors may have contributed to the displacement of the pipe, and it was not initially clear when the leak began.
Martyn Willsher, the chief executive of pipeline operator Amplify Energy, said this week that underwater observations revealed that 4,000 feet (1,200 meters) of the pipeline was not where it should be.
"The pipeline has essentially been pulled like a bowstring," he told a press conference on Tuesday.
"At its widest point it is 105 feet away from where it was," he said, adding the break was at the apex of this bend.
Willsher refused to speculate on the cause of that displacement and whether a ship's anchor could be responsible, but said: "It is a 16-inch steel pipeline that's a half inch thick and covered in an inch of concrete.
"For it to be moved 105 feet is not common."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)