Thousands of jellyfish cover shore in Florida Beach

HALLANDALE BEACH, Fla. (KABC) -- Florida's Hallandale Beach turned into a sea of jellyfish after dozens washed ashore.

Authorities posted pictures to the city's Facebook page last week. The bluish-purple jellyfish are nicknamed "blue sailors," and they are not known to sting.

The sea critters have bodies designed to allow them to sail away from shore. However, strong winds can catch the fins and carry them onto beaches.

City officials said the sea life phenomenon happens about every three years.