Chilling video shows killer whale Kasatka attacking trainer at SeaWorld San Diego

Chilling video of a killer whale attacking her trainer at SeaWorld San Diego has been released publicly six years after the attack.

The 15-minute video shows the 6,000-pound orca, Kasatka, thrashing Ken Peters underwater several times when performing a routine trick in 2006.

Britain's Daily Mail cited author David Kirby, whose freedom of information request resulted in the Sea World footage being released, as saying Kasatka attacked Peters after hearing a distress cry from her calf, Kalia, in a backstage pool.

Kirby wrote a book titled "Death at SeaWorld," which details what he says are the dangers of keeping orcas in captivity.

The attack on Peters came months before the death of Orlando SeaWorld trainer Dawn Brancheau during a live performance. Brancheau drowned after being dragged under water by a killer whale.

In the video shows, Kasatka drags Peters under water for extended periods, shaking him like a rag doll before returning him to the surface.

Peters appears to remain calm during the ordeal, and according to Kirby even managed to discourage colleagues from trying to call Kasatka off him "since it only seemed to make Kasatka bite down harder."

According to WKMG, Peters testified at an Occupational Safety and Health Administration court hearing last September — where the video was used in evidence — that he was confident the whale would let go of him if he remained calm.

Other trainers are unable to reach Peters as Kasatka appears to keep him in the middle of the pool, out of their reach.

According to CBS, the trainers tried to signal Kasatka to let Peters go, but the orca did not obey.

Peters eventually managed to scramble from the whale’s grasp, escaping over a safety net with the whale in pursuit.

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He suffered a broken foot and puncture wounds in both feet in the attack.

SeaWorld San Diego's vice president, meantime, testified that no safety improvements were made after the incident involving Peters, other than ordering trainers not to swim with Kasatka and two other orcas.

KSAT.com quoted SeaWorld as saying in a statement: "This incident was well documented and thoroughly covered by the news media in 2006. This video clearly shows the trainer's remarkable composure and the skillful execution of an emergency response plan, both of which helped result in a successful outcome with minor injuries.

"It should be noted that CalOSHA did not issue any citations to SeaWorld as a result of this incident. SeaWorld’s trainer returned to work shortly after this incident and remains a member of the team at Shamu Stadium to this day." 

Although he reportedly vowed never to swim with Kasatka, Peters continued to work at Shamu Stadium, San Diego 6 reported, citing the SeaWorld statement.  

The full video, as posted on YouTube, can be seen below. It does not have audio. Peters is dragged under for the first time about 1 minute into the video.