Up date : US Student Mauled by Chimps in Critical Condition

New details are slowly emerging in the story of the US grad student mauled by chimps at the Jane Goodall Institute Chimpanzee Eden in South Africa, including one particularly heart-wrenching:

Andrew F. Oberle ,26,an American researcher, was giving tourists a lecture at the sanctuary as part of his master's degree in Anthropology and Primatology, based at the University of Texas at San Antonio.

South African conservationist Eugene Cussons, who runs the sanctuary said, it was the first time he had asked Andrew Oberle to speak to visitors.

Cussons said Oberle broke the rules by going through the first of two fences that separate humans from the chimps. The chimps then grabbed him and pulled him under the second fence, which is electrified.Cussons said it was unclear why Oberle had moved so dangerously close.

Oberle was bitten repeatedly and dragged for nearly a kilometer (half mile).'When we found him, he was in a foetal position underneath a lapa (a roofed, open-walled structure) with massive injuries, lacerations, abrasions, partial amputation from his head to toe,' Lloyd Krause, ER24 emergency service spokesman told the Herald Sun.

Oberle was reported to be in a drug-induced coma.Oberle underwent surgery at the hospital Thursday.

Once he's well enough to talk investigators will hopefully "be able to find out why he crossed the safety fence to go on to the main fence," Cussons said.

Cussons has managed a sanctuary for abused and orphaned chimpanzees for six years founded by famed primatologist Goodall.He said the two chimps that attacked Oberle, Amadeus and Nikki, had been isolated since the attack.

Oberle's mother, Mary Flint of St. Louis, says her son knew the risks of working with chimps and would not want them blamed for the attack. She was on her way to South Africa.