Lotte World Aquarium recently filed charges against a local marine animal rights advocates' group for holding a protest within its premises, the latest development in their ongoing battle over the release of a beluga whale.

Songpa Police Station in southern Seoul last week said it is pressing charges of destruction of property and interference with business against eight activists from the group Hot Pink Dolphins, a marine conservation activist group. Last year, they held a protest at the Lotte World Aquarium in Jamsil, southern Seoul, demanding the company release its last surviving beluga, Bella, to a wildlife sanctuary.

The aquarium claimed that the adhesives used to attach the activists' banner to the interior glass had caused 700 million won ($517,000) in damages, and that their protest inconvenienced visitors and disturbed the animals. The activists claimed that the damage was greatly exaggerated.

Lotte World Aquarium had acquired three belugas from Russia upon its 2014 opening, but two of them died in 2016 and 2019, sparking accusation of animal cruelty from local environmental groups. The company vowed to move Bella to a wildlife sanctuary by the end of 2022, but has yet to do so.

Koh Jeong-rak, chief of the Lotte World Aquarium, said the company had attempted to release Bella on three separate occasions but failed each time because another species had been occupying the area at the time; due to a delay caused by the COVID-19 outbreak, and because the earlier occupant had health issues.

"We are having a discussion about releasing her (Bella) by 2026, but there can be other issues," he was quoted as saying.

Marine animal rights activists questioned the sincerity of the aquarium's intent upon the repeated delay, and has held protests for Bella's freedom.

For years, debate has been ongoing over whether highly intelligent species like cetaceans -- whales, dolphins, and porpoises -- should be allowed to live and be bred in captivity. Animal rights group International Marine Mammal Project claims that captivity shortens the lives of cetaceans, making them vulnerable to stress-induced diseases.

Whether a beluga whale's life is shortened by captivity is not definitive, as the life expectancy of the wild beluga ranges widely depending on the method of age calculation.