IMPERIAL BEACH, Calif. (AP) - San Diego County authorities say waters off Imperial Beach will be closed to swimmers for days after a pipe broke in Tijuana, Mexico, and spewed nearly 3 million gallons of sewage into the Pacific Ocean.

Mark McPherson of the county's environmental health department says sewage was going into the ocean at rate of about 1,000 gallons a minute on Wednesday. Lifeguards are keeping people out of the water at Imperial Beach, a popular spot for surfers.

The International Boundary and Water Commission says Mexican authorities expected to have the line repaired by Thursday morning. Aging infrastructure is believed to be the cause.

Imperial Beach is often closed during winter when sewage from Tijuana spills into a valley on the U.S. side of the border.

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