The rare babies are among triplets—a male and two females—born to captive leopards in June as part of a Persian leopard breeding program. About 70 live in zoos worldwide.

The big cats are native to Middle Eastern countries including Iran and Afghanistan, where, experts say fewer than 2,000 animals remain in the wild.

Researchers are striving to save the Persian leopard, which is the largest of the subspecies and is listed as endangered by the World Conservation Union.

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