HUNTINGTON BEACH, Calif. (AP) -- Orange County beaches will reopen a day after being shut down when surfers scrambled out of the water following a shark sighting.

Surfer David Charles said he was waiting for a wave Sunday at Bolsa Chica State Beach when two other surfers spotted what they thought might be a dolphin.

Charles says he saw the tail of a shark thrashing in the water right behind him. Charles and the others paddled quickly to shore.

READ MORE CBS LA: Shark Encounter At Bolsa Chica State Beach

He estimates the shark was at least six feet long.

Officials deemed the sighting credible and closed a stretch of about a mile of Bolsa Chica and Huntington State beaches. The beaches will reopen Monday.

There have been shark sightings up and down the California coast in recent months.

In October, a cluster of 20 sharks were spotted swimming off the coast of Pacifica.

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