Re: It is not unusual for a wild animal to all of a sudden do something like this.
Umm, yes it is. Stories like this happen daily with PEOPLE, but rarely with animals.
12/25/07 - Tiger escapes its cage at the San Francisco Zoo, kills one visitor and mauls two others. The same tiger was responsible for the 12/22/06 mauling of a trainer almost exactly a year ago at the zoo.
12/3/07 - A tiger at a Southern California animal sanctuary run by actress Tippi Hedren mauled a 40-year-old caretaker who was cleaning its cage, critically injuring him.
12/22/06 - A 350-pound Siberian tiger attacked and injured her trainer at the San Francisco Zoo as at least 50 visitors looked on. A man who watched the attack happen says the cat devoured most of the woman's right arm. The tiger did not let go until a zoo employee jabbed her in the head with a long pole.
10/3/03 - In one of the most famous tiger attacks to date, world famous illusionist Roy Horn was critically injured when Montecore, one of his trademark white tigers, bit him in the neck and dragged him offstage at the Mirage in Las Vegas. The entertainer was partially paralyzed from the terrifying attack.
http://wcbstv.com/seenon/tiger.attacks.timeline.2.618057.html