Hunters, drones and helicopters with thermal cameras have been deployed to find a lioness believed to be on the loose around Kleinmachnow, near Berlin, the capital of Germany.
Authorities have warned people to avoid forests and urged parents to keep children indoors.
More than 30 patrol cars were deployed after an emergency call was received around midnight.
Officials said riot police had also been deployed to protect the population and armored vehicles were seen in the vicinity.
Police said no zoos or circuses had reported missing an animal, raising the possibility it could be an escaped pet.