Police joined the search after a zoo in Texas was forced to close after a clouded leopard named Nova escaped from its enclosure.
Dallas Zoo officials stressed the animal was not a danger to humans and had likely climbed a tree, but warned locals to keep their pets inside.
The fugitive is thought to be hiding somewhere inside the 106-acre zoo, the oldest and largest in Texas.
Harrison Edell, the zoo’s executive vice president for animal care and conservation, said the search for the elusive leopard has focused on trees that felines like to climb.
Clouded leopards are wild cats native to Southeast Asia and China.
They weigh around 20-25 lbs (9-11 kg) and Mr Edel said they posed no threat.
“If anything, she was really nervous and scared of people,” he added.
Mr Edell told ABC News Nova likely escaped through a tear in the mesh around the fence, where Luna’s sister was.
The zoo’s latest call to label the incident “code blue” amassed hundreds of thousands of views on Twitter.
“Its habitat is a dense forest and it was designed for life in the treetops,” the zoo tweeted.
“It’s bigger than a house cat and smaller than most bobcats.
“If you think you see an animal, please don’t approach the animal.”
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The zoo asked that if anyone saw Nova, “they should take a picture and message us”.
“To reassure some, this animal poses no greater risk to pets if she leaves the ground than the North Texas native animals that roam our community,” it added.
“But if you feel more comfortable bringing your pet in, please do so.”
Nova is not the first person to escape from a zoo.
In 2004, a 340-pound (154-kilogram) gorilla named Jabari jumped out of his enclosure and went on a rampage in the park, injuring three people before being shot dead by police.