A 37-year-old female zookeeper at a so-called "immersion zoo" in Spain was killed by a tiger, reports the AFP. The attack wasn't witnessed, but her body was discovered about 5pm Saturday at Terra Natura animal park. "The tiger was still in the cage with the 37-year-old keeper," says a Red Cross rep. The animal was sedated with darts so that rescuers could enter, but the unnamed keeper was pronounced dead at the scene. "The entire staff of the park is appalled and deeply affected by the tragic news," a zoo rep says, via the Mirror. It's possible that the woman, a veteran employee of eight years, left a gate open as she went about her duties, per local reports. Terra Natura touts itself as a "new generation immersion park," which separates animals from tourists only with a glass barrier so that, as the Mirror puts it, visitors "can watch and be 'at one' with" the animals. (More tiger mauling stories.)