A zoo in East Tennessee is warning visitors not to bring food after one of its animals died over the weekend as a result of trying to eat trash brought in by a patron.

Lief, a male sitatunga, died after choking on a squeezable applesauce pouch at BrightsZoo in Limestone, zoo officials posted on Facebook.

The zoo is about 80 miles northeast of Knoxville, south of Kingsport.

"Today we lost a beloved animal due to choking," the zoo posted Saturday with a picture of two discarded applesauce pouches with thick, red caps. In the post, the zoo explained how the packaging is dangerous to zoo animals because the caps look like food to some animals.

Park security performs regular bag searches to prevent people from bringing items in to the zoo, officials wrote.

"Yet some people find ways to sneak these in," the post continues.

"He came to us at one year old,"  Zoo Owner David Bright told USA TODAY on Monday.

Bright said it appears someone snuck the squeezable pouch into the zoo and the lid to the pouch was tossed into Lief's exhibit.

Keepers found the animal in distress, veterinarians attempted to remove the object from Lief's airway, but the animal died during the procedure.

"He still had a lot of life to live," the zoo wrote in the comment section after throngs expressed not only anger, but condolences for the zoo's loss.

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Who brought discarded applesauce pouch into Brights Zoo?

According to zoo officials, it was not immediately known who brought the discarded applesauce pouches into the zoo.

"We would love to know the people responsible but sadly don’t think we ever will," the social media post reads.

USA TODAY has reached out to the zoo.

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What is a sitatunga?

Sitatungas, according to seaworld.org, are medium-sized antelope native to Africa. Their diet includes vegetation and they will occasionally eat fruit from fallen trees and chew the bark of trees and shrubs.

An aquatic animal found in swamps, they like to swim, according to the website, and can live around two decades in a zoo.

Guests encouraged to visit vehicles or outside picnic area to eat and drink

According to its website, Brights Zoo is a family-owned private business with animals including some endangered species including addax, bongo and scimitar-horned oryx, and bactrian camels. The center also contains more common but exotic creatures like red kangaroos, spider monkeys, pandas and zebras.

The zoo reminded guest who want to eat or drink, they can visit their vehicles or picnic areas in the zoo's parking lot and re-enter the zoo.

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.