San Francisco's Ocean Beach looked the set of a horror movie this weekend with the title "Invasion of the Jellyfish."
People who went to the beach early Saturday found tens of thousands of jellyfish washed ashore. The jellyfish stretched about three miles from Pacheco to Lawton Streets.
"There was a large swell overnight that may have been responsible," National Park Service spokesman George Durgerian told Bay City News Saturday.
Durgerian described the site like a cobblestone walkway. He said they were the common breed of moon jellyfish, but added the number of them was very uncommon. The last time this happened, according to Durgerian was seven years ago.
The creatures will left alone and most were brought back out to sea by the high tide.
Durgerian told Bay City News a state biologist will investigate the find later this week.