Whiting Ranch Wilderness Park in Orange County will be closed until further notice, an OC Parks spokesperson told Eyewitness News.
A family hiking in the Four Corners area of the park saw the big cat Sunday afternoon and determined the lion was stalking a young girl in the group.
A park employee nearby scared the animal away.
While the location in the Trabuco Canyon area remains closed, rangers will monitor whether the lion heads back into more rural territory.
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Those who neighbor the park in Modjeska Canyon suspect this is the same animal they've caught wandering their neighborhood.
The trouble there started on Thanksgiving as livestock were found dead in the months that followed.
One neighbor captured a video of a mountain lion jumping through front yards on an early December morning.
In the latest sighting, a cougar killed Jim Carter's llama at the start of February. Carter says a week earlier, another weighing about 300 pounds was dragged off his property.
"This really keeps me from hiking in the forest, at least toward the evening hours, with my dog," Carter said.
Carter and his neighbors believe the same cat is responsible for the dead animals.
And with the latest encounter over the weekend at Whiting Ranch and a history of cougar attacks on humans at the wilderness park - the latest a 3-year-old-boy who survived - local residents want action taken now.
But state Fish and Wildlife officials say there is no proof the animal made the kills.
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