A giant anaconda, recently discovered and thought to be among the largest in the world, has been found dead, media reports said.

A snake expert involved in its initial identification suggested that a gunshot wound might be responsible.

The massive reptile, named Ana Julia, was discovered in the Formoso River in the rural region of Bonito, located in the Mato Grosso do Sul State in southern Brazil, approximately five weeks ago, reported the Independent.

The species was encountered during the filming of the National Geographic's Disney+ series 'Pole to Pole' featuring Will Smith.

Weighing around 440 pounds (equivalent to 31 stone) and measuring a staggering 26 feet in length, the northern green anaconda’s head was comparable in size to that of a human.

While speculation circulates about the possibility of the snake having been shot, a Dutch researcher who participated in Ana Julia's discovery stressed that investigation into the cause of death were underway.

Professor Freek Vonk conveyed the unfortunate development via Instagram.

He wrote, "With enormous pain in my heart I want to let you know that the mighty big green anaconda I swam with was found dead in the river this weekend."

"An iron-strong animal, a survivor, one that's been swimming around Bonito for decades," the professor added.

"As far as we know, she was super healthy and still in the prime of her life, and in the coming years she could have taken care of many descendants. Since there are not so many of this species of colossal giant snakes swimming around, the blow to biodiversity (and this particular species in particular) is also huge," he added.

Professor Vonk had previously stated that the snake was shot dead, but has now clarified that authorities have not yet found any evidence supporting this claim.

"The cause of death is currently still being investigated, considering all possible options. So it's also possible that she died a natural death," he said.

At the time of discovery, Professor Bryan Fry from The University of Queensland said: "The size of these magnificent creatures was incredible - one female anaconda we encountered measured an astounding 6.3 metres long

"There are anecdotal reports from the Waorani people of other anacondas in the area measuring more than 7.5 metres long and weighing around 500 kilograms."