sentences:  Zhang Jiao of central Anhui province, like the previous two trespassers, sustained bite injuries to his legs and was hospitalized, where he had surgery for damage to major ligaments.According to witnesses, Zhang appeared to first look around to see if pandas were nearby before jumping in to get his 5-year-old son's toy.Zoo workers were forced to use tools to pry Gu Gu's jaws apart when he wouldn't let go of Zhang's legs.