At least (only "20 visitors") this wasn't the`San Diego Zoo. Q: Were visitors allowed in the locked buildings along with the employees? Link: My Way News - Human Role Not Ruled Out in Tiger Attack.
SAN FRANCISCO (AP) - The big cat exhibit at the San Francisco Zoo was cordoned off as a crime scene Wednesday as investigators tried to determine whether a Siberian tiger that killed a visitor escaped from its high-walled pen on its own or got help from someone, inadvertent or otherwise. Police shot the 300-pound animal to death after a Christmas Day rampage that began when the tiger escaped from an enclosure surrounded by what zoo officials said are an 18-foot wall and a 20-foot moat. Two brothers who also were visiting the zoo were severely mauled.
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About 20 visitors were in the zoo when the attacks happened about an hour before the 6 p.m. closing time, officials said. Employees and visitors were told to take shelter when zoo officials learned of the attacks, and some employees locked themselves inside buildings as they had been instructed to do if an animal escaped.
