OCEANSIDE, Calif. - For the second time in less than a week, a 'sea serpent' has attracted gawkers on a Southern California beach.

This time the rare, snakelike oarfish washed up Friday afternoon in Oceanside.

The newspaper U-T San Diego reported that it measured nearly 4.3 metres long and attracted a crowd of up to 75 people.

Oceanside police contacted SeaWorld San Diego, The Scripps Research Institute and the National Oceanic and Atmospheric Administration. Someone from NOAA retrieved the carcass, which was cut into sections for later study.

While it's unusual to find the deep-water fish near shore, on Sunday a snorkeler off Catalina Island found an 18-foot (5.5-meter)-long oarfish and dragged it onto the beach with the help of a dozen other people.

According to the Catalina Island Marine Institute, oarfish can grow to more than 15 metres, making them the longest bony fish in the world.

They are likely responsible for sea serpent legends throughout history.