Updated 9:17 p.m. A female intern-volunteer was killed Wednesday by a lion at a private wild animal park in Central California, and state and local authorities were trying to determine what might have caused the fatal attack. Cat Haven founder and executive director Dale Anderson was crying as he read a one-sentence statement about the fatal mauling at the exotic animal zoo he has operated since 1993. The 26-year-old intern was attacked and killed when she entered the lion's enclosure, Anderson said, but he refused to answer questions or provide more details. Sheriff's deputies responding to an emergency call from Cat Haven, in the Sierra Nevada foothills about 45 miles east of Fresno, found the woman severely injured and still lying inside the enclosure with the lion nearby, Fresno County sheriff's Lt. Bob Miller said. Another park worker had unsuccessfully tried luring the lion away and into a separate pen, so deputies shot and killed it so they could reach the wounded woman, who died at the scene, Miller said. Investigators were trying to determine why the intern was inside the enclosure and what might have provoked the attack, sheriff's Sgt. Greg Collins said. The facility is normally closed on Wednesdays, and only one other worker was there when the mauling happened, Collins said. CBS affiliate KGPE reports that there had been no problems at Cat Haven prior to the incident, according to authorities.