SAN ANTONIO – The Texas Biomedical Research Institute is offering an explanation about how four baboons were able to escape the facility on Saturday.

According to a press release, the baboons are housed in an open-air enclosure that is surrounded by perimeter walls that are angled inward.

The baboons rolled a 55-gallon barrel to an upright position and used it to climb out of the housing structure.

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The barrels were in the enclosure because they are used as an enrichment tool for the animals, but after Saturday's escape, the barrels have been removed from the enclosure.

Three of the baboons were recaptured within 20-30 minutes of escaping. The fourth baboon returned to the enclosure on his own.

KSAT viewers sent pictures and video of a baboon running along the road.

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“The animal care team held two of the three baboons to the tree line, while members of the animal capture team followed one baboon along the street and used verbal and hand signaling commands to corral the baboon to the tree line for its safety and efficient capture,” said Dr. Bernal, DVM, attending veterinarian at SNPRC.

The animal capture team members were wearing protective equipment, including masks, while they pursued the escaped baboons. Some residents had expressed concern about whether the animals carried infectious diseases. SNPRC said the animals were not part of an active study and they were following protocol by wearing the protective equipment. SNPRC says the baboons are susceptible to human illnesses.

All of the escaped baboons were unharmed and are said to be doing well.

SNPRC has more than 2,500 animals on the Texas Biomed campus. They are used to study diseases, drug therapies and vaccines.

“We have been caring for research baboons for more than 50 years. We have nearly 1,100 baboons on the property that date back eight generations. Baboons, as with all our animals, are critical to biomedical research. Baboons, in particular, have played an important role in the discovery of life-saving drugs, therapies and vaccines and have led to greater understanding of chronic diseases like heart disease, diabetes, obesity, osteoporosis and so much more that impact the lives of millions of people," said Lisa Cruz, assistant vice president for communications.