Beachgoers were seen poking a venomous Portuguese man o' war jellyfish after several of them washed up on a beach, prompting authorities to take action.

Footage shows a man tapping one of the creatures, also known as box jellyfish, with a long metal pair of tongs in the city of Wenchang on the island of Hainan in China on January 20.

Moments later another person poked the marine animal with a plastic straw after it came ashore at Sun Bay Beach.

The Portuguese man o' war contains numerous venomous tentacles that deliver a painful sting powerful enough to kill fish and have been known to kill humans.

Chinese media revealed that several beachgoers were strolling along the seashore when they suddenly came across the creature, which they first believed was a blue plastic bag.

After realising that it was a Portuguese man of war jellyfish, whose sting packs a painful punch and causes welts on exposed skin, they immediately called authorities.

By the time the team of specialists arrived on-site, there were reportedly more than 20 jellyfish of the same variety present on the beach.

After getting rid of the jellyfish, the team launched a public warning to prevent tourists from visiting the beach and set up warning signs in the same area.

The Portuguese man o' war jellyfish is one of the world's deadliest sea creatures.

They are not typically found in China. Their usual habitat is in warmer waters, such as the Atlantic, Indian, and Pacific Oceans, especially in tropical and subtropical regions.

However, there have been rare instances of them being spotted off the coast of southern China, near Hong Kong and the South China Sea.