KNOXVILLE, Tenn. (AP) - Knoxville Zoo visitors were the ones confined after a 350-pound lioness nudged open a gate.

Zoo spokeswoman Tina Rolen told The Knoxville News Sentinel (http://bit.ly/VQgp7Y ) visitors were never in danger Sunday because Zarina the lioness never got out of the lion habitat building.

Still, visitors were hustled into zoo buildings as a precaution.

Keepers used a tranquillizer dart to subdue Zarina and then moved her to her own habitat section of the building. The event lasted about a half-hour.

Information from: The Knoxville News Sentinel, http://www.knoxnews.com

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