A man who was severely mauled by two chimpanzees at an animal sanctuary last week was quickly overwhelmed when the apes attacked, his wife said Monday.

"One was at his head, one was at his foot. But all that time ... he was trying to reason with them," a sobbing LaDonna Davis told ABC's "Good Morning America." "I couldn't do anything."

Davis, 64, and her husband, St. James Davis (search), were visiting Animal Haven Ranch (search) near Bakersfield on Thursday when two male chimps escaped their enclosure and attacked the couple.

"When we made eye contact, the charge was on," LaDonna Davis said. "There was no stopping anything, and the big chimp came around from behind me and pushed me into my husband. The male came around from behind and chomped off my thumb. ... My husband must have realized we were in deep trouble because he pushed me backward. At that time, they both went for him."

St. James Davis, 62, lost all the fingers from both hands, an eye, part of his nose, cheek, lips and part of his buttocks in the ferocious attack, his wife said over the weekend on NBC's "Today Show." She also said one of his feet was mutilated. A Kern County Sheriff's commander also said his genitals were mauled.

St. James Davis was being treated at Loma Linda University Medical Center (search), where doctors said his condition was "minute by minute," his wife said Monday.

"Right now what they are trying to do is keep his breathing constant," she said. "That's all they can tell me, but I told him that he can't leave me. He has to be strong."

The Davises were visiting the sanctuary to celebrate the birthday of Moe — a 39-year-old chimpanzee who was taken from their home in West Covina, a Los Angeles suburb, after biting off part of a woman's finger in 1999.

Authorities were continuing to investigate how the two chimps, named Ollie and Buddy, got loose. Both were shot and killed during the attack.