A family outing ended in terrifying circumstances after a massive octopus latched onto a young boy and climbed outside its water tank while wrapping itself around the child.

The six-year-old was innocently interacting with the sea creatures above an open-top pool when the octopus grabbed him by the arm, suctioned itself to his torso and would not let go.

Staff and onlookers at the San Antonio Aquarium in Texas rushed to assist the child, and it reportedly took three adults at least five minutes to physically remove the tentacles, leaving the youngster severely bruised on the arm and upper body.

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The child’s mother, Britney Taryn, said the incident, which occurred during a visit by her family on July 14, happened when the giant Pacific octopus grabbed her son Leo’s arm while he was hovering over the touch tank.

Ms Taryn released a TikTok video saying they had previously visited the attraction and engaged with the same octopus without issue.

“My son is very level-headed when it comes to animals, so when he had his arm in there, and he starts saying, ‘Mom, it’s not letting me go — and way too calmly — ‘I’m like, ‘Oh, okay.’ So I’m helping him get down from the step and trying to pull him away from the octopus, and that octopus is not letting go,” Ms Taryn said.

“The octopus starts coming out of the tank, and the reason we don’t have pictures or videos of this is because my friend was also freaking out.”

Images released on social media show the young boy’s arms covered in deep bruises caused by the Octopus’s suction cups.

The San Antonio Aquarium has since posted a social media video explaining the bruising these animals can inflict once they attach themselves to other animals or humans, that can last between seven to 14 days.

“So there’s around 200 suction cups per arm. And as they grow ... they will actually shed their suction cup,” an aquarium employee said in the clip.

The aquarium added that the giant Pacific octopus has the ability to lift weights of over 300 kilograms.

According to PEOPLE, Ms Taryn has attempted to engage with the aquarium and is campaigning for safer and more comfortable living conditions for the animal, as well as others in similar situations.

She added that she asked the San Antonio Aquarium to formally document the incident, and to provide an accessible explanation of the aquarium’s safety protocols for when visitors interact with animals.

In a social media video she claimed that she had not heard back from the Texas-based venue.