These 'deadly' sea creatures have been washing up on the shores or beaches across the north west following a period of stormy weather.
The creature, which looks like a fluorescent jellyfish, was spotted on the beach at Lytham St Anne's in Lancashire and experts have warned people not to touch them if they find one.
It comes after they were also found on Preesall beach in Lancashire and Ainsdale beach in Merseyside.
The strange creature is a Portuguese Man o' War - also known as the man-of-war, bluebottle, or blue bottle jellyfish, Lancashire Live reports.
On Monday (November 8), the Royal National Lifeboat Institution urged people to stay away from the creatures as they can give a nasty sting, even after they have died.
Their tentacles contain venom that is capable of paralysing and killing small fish and crustaceans.
A sting can cause nasty welts on exposed skin and, in rare cases, they have the potential to kill a human.
Although it has the appearance of a jellyfish, the Portugese Man o' War is actually a species of siphonophore and isn't one animal but a mass of small organisms called zooids.
The genetically identical organisms are divided into four specialised parts, each of which is responsible for a specific task - floating, capturing prey, feeding or reproduction.
The creatures are mainly found in the Pacific Ocean but can also be spotted in the Atlantic Ocean and the Indian Ocean.
A Wildlife Trust Facebook page posted a warning about the creatures after they were found on the Fylde coast.
The post on the Fylde Sand Dunes page said: "Look at what's washed up on the shore at St Anne's! It's not a jellyfish, it's a Portuguese Man O War!
"This isn't one animal, but a mass of smaller animals called zooids, which live together as a single floating colony.
"They have a sail and gas bladder which allows them to be carried along ocean currents without having to use any energy! Unfortunately this also means that they have no control over where they drift, and can be stranded after being blown ashore by strong winds.
"After last week's stormy weather, Man O War have been spotted all over the North-West!
"If you do see one though, don't touch! They have a painful sting which they use to catch fish, but their tentacles can still sting after they are dead!"
