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A SeaWorld killer whale snatched a trainer from a poolside platform Wednesday in its jaws and thrashed the woman around underwater, killing her in front of a horrified audience. It marked the third time the animal had been involved in a human death.

Distraught audience members were hustled out of the stadium immediately, and part of the park was closed.

Trainer Dawn Brancheau, 40, was rubbing Tilikum after a noontime show when the 12,000-pound whale grabbed her and pulled her in, said Chuck Tompkins, head of animal training at all SeaWorld parks. Park officials say the veteran trainer drowned.

Audience member Eldon Skaggs said Brancheau's interaction with the whale appeared leisurely and informal at first. But then the whale "pulled her under and started swimming around with her," he told The Associated Press.

Skaggs, 72, said an alarm sounded and staff rushed the audience out of the stadium as workers scrambled around with nets.

Skaggs said he heard that during an earlier show the whale was not responding to directions. Others who attended the earlier show said the whale was behaving like an ornery child.

He left with his wife and didn't find out until later that the trainer had died. The retired couple from Michigan had been among some stragglers in the audience who had stayed to watch the animals and trainers when the accident occurred.

"We were just a little bit stunned," said Skaggs' wife, Sue Nichols, 67.

Another audience member, Victoria Biniak, told WKMG-TV the whale "took off really fast in the tank, and then he came back, shot up in the air, grabbed the trainer by the waist and started thrashing around, and one of her shoes flew off."

Two other witnesses told the Orlando Sentinel that the whale grabbed the woman by the upper arm and tossed her around in its mouth while swimming rapidly around the tank. Brazilian tourist Joao Lucio DeCosta Sobrinho and his girlfriend were at an underwater viewing area when they suddenly saw a whale with a person in its mouth.

The couple said they watched the whale show at the park two days earlier and came back to take pictures. But on Wednesday the whales appeared agitated.

"It was terrible. It's very difficult to see the image," Sobrinho said.

Because of his size and the previous deaths, trainers were not supposed to get into the water with Tilikum, and only about a dozen of the park's 29 trainers worked with him. Brancheau had more experience with the 30-year-old whale than most, and was one of the park's most experienced trainers overall.

"We recognized he was different," Tompkins said. He said no decision has been made yet about what will happen to Tilikum, such as transferring him to another facility.

A SeaWorld spokesman said Tilikum was one of three orcas blamed for killing a trainer in 1991 after the woman lost her balance and fell in the pool at Sealand of the Pacific near Victoria, British Columbia.

Steve Huxter, who was head of Sealand's animal care and training department then, said Wednesday he's surprised it happened again. He says Tilikum was a well-behaved, balanced animal.

Tilikum was also involved in a 1999 death, when the body of a man who had sneaked by SeaWorld security was found draped over him. The man either jumped, fell or was pulled into the frigid water and died of hypothermia, though he was also bruised and scratched by Tilikum.

Later Wednesday, SeaWorld also suspended the killer whale shows at all of its parks, which also include locations in San Diego and San Antonio, to review procedures.

According to a profile of Brancheau in the Sentinel in 2006, she was one of SeaWorld Orlando's leading trainers. It was a trip to SeaWorld at age 9 that made her want to follow that career path. Dawn was the youngest of six children who grew up near Cedar Lake, Ind.

"I remember walking down the aisle (of Shamu Stadium) and telling my mom, 'This is what I want to do,"' she said in the article.

Brancheau worked her way into a leadership role at Shamu Stadium during her career with SeaWorld, starting at the Sea Lion & Otter Stadium before spending 10 years working with killer whales, the newspaper said.

She also addressed the dangers of the job.

"You can't put yourself in the water unless you trust them and they trust you," Brancheau said.

Brancheau's older sister, Diane Gross, said the trainer wouldn't want anything done to the whale because she loved the animals like children. The trainer was married and didn't have children.

"She loved the whales like her children, she loved all of them," said Gross, of Schererville, Ind. "They all had personalities, good days and bad days."

Gross said the family viewed her sister's death as an unfortunate accident, adding: "It just hasn't sunk in yet."

Steve McCulloch, founder and program manager at the Marine Mammal Research and Conservation Program at Harbor Branch/Florida Atlantic University, said the whale may have been playing, but it is too early to tell.

"I wouldn't jump to conclusions," he said. "These are very large powerful marine mammals. They exhibit this type of behavior in the wild.

Tompkins, the SeaWorld head trainer, said of the whale: "We have no idea what was going through his head."

Mike Wald, a spokesman for the Occupational Safety and Health Administration office in Atlanta, said his agency had dispatched an investigator from Tampa.

Wednesday's death was not the first attack on whale trainers at SeaWorld parks.

In November 2006, a trainer was bitten and held underwater several times by a killer whale during a show at SeaWorld's San Diego park.

The trainer, Kenneth Peters, escaped with a broken foot. The 17-foot orca that attacked him was the dominant female of SeaWorld San Diego's seven killer whales. She had attacked Peters two other times, in 1993 and 1999.

In 2004, another whale at the company's San Antonio park tried to hit one of the trainers and attempted to bite him. He also escaped.

Wednesday's attack was the second time in two months that an orca trainer was killed at a marine park. On Dec. 24, 29-year-old Alexis Martinez Hernandez fell from a whale and crushed his ribcage at Loro Parque on the Spanish island of Tenerife. Park officials said the whale, a 14-year-old named Keto, made an unusual move as the two practiced a trick in which the whale lifts the trainer and leaps into the air.

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