Apple Valley, MN (Learfield Wire Services) - A popular tiger at the Minnesota zoo has died unexpectedly. Officials say three-year-old Nadya passed away over the weekend.

The Amur tiger had been sick in the week leading up to her death. She died soon after an emergency surgery to determine the cause of her illness.

Nadya arrived in Minnesota from the St. Louis zoo in 2012.

Minnesota Zoo Vice President Kevin Willis says “we are very sad over the unexpected passing of Nadya. Because she was hand raised here, she was one of our favorite animals and despite receiving the very best in medical care, she unfortunately didn’t survive. She will always be remembered by staff and volunteers as a sweet-natured tiger.”

Blood tests prior to her death showed compromised liver function. The results of an animal autopsy are pending.

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