A SeaWorld employee posed for three years as an animal rights activist, in an apparent attempt to undermine protests against the company over its use of captive killer whales, according to an investigation by People for the Ethical Treatment of Animals (PETA).

The group publicized evidence this week that suggests 28-year-old Paul T. McComb, under the name “Thomas Jones,” infiltrated the anti-SeaWorld protest movement, allegedly joining PETA’s Action Team using a P.O. Box in San Diego that was registered to Ric Marcelino, the director of security for SeaWorld San Diego.

McComb, who Bloomberg reports has worked in a number of positions at SeaWorld since at least 2008, including as a human resources representative, attended organizational meetings and “constantly ‘fished’ for information from PETA staffers about protests against SeaWorld,” PETA claims.

SeaWorld, which owns 11 theme parks in the U.S., has experienced a public-relations backlash since the release of the Blackfish documentary in 2013, which delved into problems within the sea-park industry.

According to PETA, McComb joined a protest of SeaWorld’s float in the 2014 Rose Parade.

“But, while he was arrested and taken to jail with the other protesters who sat down in front of the float, he suddenly vanished when the other protesters were booked and later released on bail. ‘Jones’ was inexplicably released without charges, and his name never even appeared on arrest sheets,” the investigation found.

“But most insidiously, he has repeatedly tried to incite people who object to SeaWorld to act illegally,” the animal rights group reports. “He even organized his own ‘direct action’ protest—one advertised as ‘more exciting than just holding signs’—only to be absent on the day of the demonstration. All of this leaves no doubt that SeaWorld is a dirty tricks corporation, devoid of ethics.”