In a statement issued Thursday, SeaWorld said its management team had a "practice in which certain employees posed as animal rights activists in connection with efforts to maintain the safety and security of company employees, customers and animals."

The practice was in response to credible threats the company said it received.

The statement said an independent group conducted an investigation and determined the practice was no longer necessary.

Protests against SeaWorld reached its height around the time the film "Blackfish" was released.

The 2013 documentary takes a critical look at the way SeaWorld raises orcas, from how they are captured as babies and the conditions they live in.

"To promote its bias that killer whales should not be maintained in a zoological setting, the film paints a distorted picture that withholds from viewers key facts about SeaWorld," the water park said in a 2013 statement in response to the film.

In 2015, PETA said it caught SeaWorld human resources employee Paul McComb posing as activist "Thomas Jones" and posting "inflammatory messages on social media, such as 'burn (SeaWorld) to the ground' and 'drain the new tanks at #SeaWorld,' in an attempt to incite illegal actions."

The organization also said McComb made multiple efforts to encourage PETA members to act illegally.

"We recognize the need to ensure that all of our security and other activities align with our core values and ethical standards," CEO Joel Manby said in SeaWorld's Thursday statement. "As always, the security and well-being of our employees, customers and animals remain at the forefront of our business practices."