A lion that killed a 24-year-old female volunteer intern may have escaped its cage before the attack, the Fresno County Coroner said on Thursday.
Dianna Hanson began a six-month internship in January at Project Survival’s Cat Haven sanctuary in Dunlap, Calif. She died Wednesday after an adult male African lion attacked her.
An autopsy showed Hanson died instantly of a broken neck, likely from a swipe of the lion's paw. The coroner said other injuries to Hanson's body happened after she died.
Before the coroner's report on Thursday, it was unclear why Hanson was so close to the big cat. The lion escaping from its cage while Hanson cleaned the main enclosure could explain that, though officials said the investigation is still ongoing.
More: Father: Lion Attack Victim Had "Her Dream Job" at Sanctuary
Hanson -- who celebrated her 24th birthday in February -- was remembered by her colleagues as "vivacious."
"Her passion for working with these animals was contagious. Dianna performed her regular scheduled duties, which included cleaning enclosures," Cat Haven founder Dale Anderson said, reading from a prepared statement Thursday.
Authorities said the 24-year-old's body was found inside the African lion enclosure.
The lion – named Cous Cous – may have broken free from his cage to kill Hanson inside a cleaning enclosure, NBC affiliate KSEE 24 News reports, citing the coroner.
The animal was shot and killed after the attack, according to the Fresno County Sheriff’s Department.
Before her internship at the sanctuary, Hanson had previous zoo keeper experience, including with big cats. Her family said it was Hanson's dream to one day with the animals, and the victim's colleagues said that passion shined through her work.
"She was doing what she loved and she did it with joy everyday she worked here," Wendy Dabbas, president of Cat Haven, said through tears Thursday.
"She’s going to be missed. I’m so sorry this has happened."
Cous Cous lived at the sanctuary since he was a cub and shared a habitat with Pely, a female lion who could be heard making deep, bark-like noises inside her enclosure on Thursday.
Anderson said the animal was nearby at the time of the attack, and is likely making those sounds because she is stressed.
Cat Haven was closed for its regular winter hours at the time of the attack, authorities said. The Sheriff's Department and state wildlife officials will both investigate the incident.