KNOXVILLE - Zoo Knoxville is investigating the mysterious deaths of 33 reptiles. 

According to a news release from the zoo, when staffers entered the building Wednesday morning they found 30 snakes and one lizard unresponsive.

Zoo clinic staffers and veterinarians from the UT College of Veterinary Medicine responded. Surviving animals were evacuated and given oxygen, while others were checked for heartbeats using ultrasound.

Of the 52 animals housed in the building, 33 died, including three critically endangered species.

"It's devastating. It's a lot bigger than just the individual snake in our collection," Zoo Knoxville director of animal care, conservation and education Phil Colclough said. "All these are pieces to a larger conservation puzzle and in some cases with these animals, there might be a handful of them left in the world."

Zoo Knoxville has taken the building in question out of use while the deaths are being investigated. The other buildings in the zoo's reptile facility were not impacted and are still open to the public. 

“These animals were important ambassadors who helped so many people understand the role snakes and lizards play in the balance of nature. We also lost breeding programs for several endangered and threatened species," New said. "It is especially difficult for our herpetologists who have dedicated their careers to caring for and advocating for these animals.”