Killer snails have plunged a city in Florida into lockdown.

Deadly snails are on the loose in Florida

Deadly snails are on the loose in Florida

A giant African land snail has been found in Miramar, 20 miles north of Miami, and authorities have set up a quarantine area to tackle the invasive species.

The snails can grow up to eight inches long and are capable of consuming at least 500 plant types with their voracious appetites.

Officials plan to spray the affected area with the chemical snail bait metaldehyde in order to kill off any more of the pests.

Miramar residents will be allowed to leave the area but will not be able to carry any plant-based supplies that could be carrying tiny eggs.

William Kern, an entomologist at the University of Florida, told Miami's Local 10 news station: "The primary danger is that they're voracious plant eaters, so they can do an awful lot of damage to both landscapes and to agriculture.

"If the snails crawl on uncooked vegetables, you can have a problem with it getting a human infection. With any invasive species, if you find it early, you may be able to control or eliminate it."