Tilikum, an orca that killed one of its trainers and featured in a documentary that swayed public opinion against holding killer whales in captivity, died yesterday.

The orca, which suffered a bacterial lung infection, had been kept for 25 years by SeaWorld, an American theme park company.

In a lengthy statement, the company said the whale, which was almost seven metres (23ft) long and weighed 11,800 pounds, had faced some “very serious health issues”. “The SeaWorld family is deeply saddened to announce that one of its most well-known orcas, Tilikum, has passed away,” it read. “Tilikum passed away early this morning surrounded by the trainers, care staff and veterinarians that provided him around-the-clock world-class care.”