"Fish and Wildlife has trained our officers in California to recognize a lion kill due to our abundance of mountain lions," Hadden said, noting that the coordination between the two camps follows a protocol set up in case of a mountain lion attack.

"We never in our wildest imagination thought it would be an African lion."

Fatal lion maulings are rare in the United States, though not unprecedented.

Twenty people, including five children, have been killed by big cats in the United States in the past 21 years, according to figures kept by Big Cat Rescue, a nonprofit cat sanctuary in Tampa, Florida.

Another 246 people were mauled in the United States during that same time period, 1990 to 2011, the group said.

The attacking lion, Cous Cous, was one of Dianna Hanson's favorites, according to her father. The lion was also a celebrity of sorts, having appeared on Ellen DeGeneres' television show when he was about 3 months old.

That said, noted animal expert Jack Hanna said any big cat can be unpredictable in the way it reacts to what it sees or hears.

"They are wild animals, end of story," he said. "No matter what anyone says, they are wild animals."