Extensive corrosion shown in photos of oil pipeline that spilled crude on Santa Barbara shore

An engineer says photos of the pipeline that spilled oil on the Santa Barbara coast show extensive corrosion and provide clues about the rupture's cause.

The pictures released to The Associated Press on Monday under a California Public Records Act request show the 8-inch tear that spilled up to 101,000 gallons of oil May 19, polluting beaches, and killing hundreds of birds and marine mammals.

Civil engineer Robert Bea (bee) says the amount of corrosion visible and the documented wear inside the pipe lead him to believe the pipe burst during a pressure spike when the operator restarted pumps that had failed earlier in the day.

Plains All American Pipeline has declined to discuss the cause of the spill while it's being investigated by federal regulators and local, state and U.S. prosecutors.