I found a link to the story here:

http://www.npr.org/templates/story/story.php?storyId=12623090

A Tortoise's Great Escape

Morning Edition, August 9, 2007 · A rare tortoise disappeared from a Virginia zoo. It's not clear whether a visitor freed it or it slipped out on its own, but it was gone. The Burmese Mountain Tortoise raced away with the speed a tortoise is famous for. Zoo staff found it seven hours later in a patch of bamboo just 20 yards from its pen.