The first attack occurred Sunday at Wesa-A-Geh-Ya, a private tiger refuge near Warrenton, some 50 miles east of St. Louis, the St. Louis Post-Dispatch reported. Jacob Barr, 26, a first-time volunteer, was attacked as he and another volunteer cleaned out a cage.

On Monday, Dakota Ramel, 16, an employee at Predator World in Branson, Mo., was mauled by three tigers as he tried to take a picture for a visitor, KSPR-TV, Springfield, Mo., reported.

At Wesa, Sandra and Tony Smith, the owners, shot and killed the tiger.

"When I shot that animal, my heart just died," Sandra Smith said. "I knew it had to be done."

Smith at first told the newspaper that she and her husband would surrender the tigers and have them put down. But on Monday, she said she was not prepared to give up the animals.

In the Predator World Attack, Stone County Sheriff Richard Hill said investigators were trying to determine if the attack was set off by something the victim did.