US Student Mauled by Chimps in Critical Condition Andrew Oberle broke the rules by going through the first of 2 fences By Kate Seamons, Newser Staff Posted Jun 30, 2012 12:43 PM CDT 14 comments Comments In this photo taken Feb. 1, 2011, chimpanzees sit in an enclosure at the Chimp Eden rehabilitation center, near Nelspruit, South Africa. (AP Photo/Erin Conway-Smith) (Newser) – 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 one: Conservationist Eugene Cussons said it was the first time he had asked Andrew Oberle to speak to visitors. Oberle, 26, was giving a lecture to about a dozen tourists when the male chimps attacked. In the end, Cussons, who was himself attacked by a chimp as he tried to pull it off Oberle, took the extreme step of firing into the air, scaring the animals away. Cussons tells the AP that Oberle broke the rules by going through the first of two fences that separate humans from the chimps, which can weigh about 150 pounds. The chimps then grabbed him and pulled him under the second fence, which is electrified; he was bitten repeatedly and dragged for nearly half a mile. Cussons said it was unclear why Oberle dared get so close. Oberle remains in critical condition; 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.