Portuguese man o'war have washed up on beaches in parts of Britain sparking warnings from wildlife experts.
This creature, often mistaken for a jellyfish, can stretch its tentacles up to an incredible 160ft long and can kill a human even if the creature is dead.
Man o'wars, also known as bluebottles for their purple bodies, can deliver excruciatingly painful stings but are rarely deadly to humans.
Incidents are rare, but stormy weather has driven these creatures up from their usual open seas territory to the shallow waters of Britain's coastline.
They have no independent means of movement and often move with the winds or sea currents. They are known to wash up on British shores between September and December.
Where have they been spotted?
Nicknamed as "Floating Terror", these creatures have been spotted near tourist areas in Cornwall, Sennen Beach and Porteras Cove.
Man o'wars can be in groups of up to 1,000. People are urged not to approach these creatures and to divert any pets from any found on beaches.
A Wildlife Trust spokesman said: "First of all, the Portuguese man o'war is not a jellyfish. It is a colonial hydrozoan, made up of small individual animals called zooids - each with their own specific function, e.g. feeding or breeding.
"They can't live separately and function together as one 'animal'.
"The Portuguese man o'war lives at the surface of the open ocean, held afloat by a gas-filled bladder. This has a crest-like structure at the top which acts as a sail.
“They can’t swim and are at the mercy of the winds — which is why they often end up washed ashore after big storms.
“They are fearsome predators, catching small fish and crustaceans with their long stinging tentacles.
"It’s these tentacles that you need to watch out for too — they can sting long after the animal has died.”
A version of this article originally appeared on NationalWorld.com