WASHINGTON (AP) — The Smithsonian’s National Zoo says its 6-year-old Andean bear Billie Jean has given birth to twins.

The cubs were born early Thursday morning. Their father was Nikki, who was euthanized in August after being treated for an aggressive type of cancer.

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The zoo says Billie Jean will stay inside with her cubs. If they are healthy, the three animals will go out into their yard in the spring.

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Andean bears are one of the world’s most endangered bear species. They have a high mortality rate for newborn cubs.

The zoo says the captive population has experienced a lull in the past six years. These cubs are the only surviving Andean cubs in a North American zoo since Billie Jean’s first cubs, Bernardo and Chaska, were born in 2010.

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