ORLANDO, Fla. - 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.

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.

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.

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.