Terror like a swimmer bitten by a deadly blue-ringed octopus at Chinaman Beach in Mosman

A woman has been bitten by a deadly blue-ringed octopus on a popular Sydney beach.

The woman, 30, picked up a shell the creature was in while swimming at Chinaman Beach in Mosman at about 2:45 p.m. Thursday.

The little blue-ringed octopus fell and bit her on the stomach twice.

Paramedics were called to the beach and applied pressure and cold compresses to the woman after she reported feeling abdominal pain around the sting area.

She was subsequently transferred to the Royal North Shore Hospital in a stable condition for observation and further treatment.

A woman in her 30s was bitten twice on the stomach by a deadly blue-ringed octopus (pictured)

“The bite of the blue-ringed octopus is a rare call for us, but it is extremely toxic,” NSW Ambulance Inspector Christian Holmes said in a statement following the incident.

The bite of the blue-ringed octopus is venom strong enough to kill more than 20 people despite the marine creature’s small size, usually around 8 cm in length.

The poison, called tetrodotoxin, causes paralysis, slowing the body to the point where it can no longer breathe and not get enough oxygen.

It is known to be 1,000 times more toxic to humans than cyanide.

There is no antidote to tetrodotoxin, as bite victims are only able to tolerate the venom in a respirator until its effects wear off.

The woman found a shell with an octopus in it while swimming at Chinaman Beach (pictured) in Mosman

The bite of the blue-ringed octopus is venom strong enough to kill more than 20 people despite the sea creature’s small size (stock photo)

While there is serious danger, there have been only a few confirmed victims of a blue ringed sting as the creatures are more likely to hide in small crevices rather than attack.

Sea slugs usually only bite if they feel threatened or have been removed from their environment.

Their blue rings only appear when the animal feels threatened.