An unidentified insider close to the investigation said it appeared one or more individuals broke into the tiger's cage at the Three Gorges Forest Wild Animal World and brutally killed the animal, Xinhua reported Saturday.

"It is highly possible that the killer or killers broke into the room, anesthetized the tiger, opened the cage and then dragged the animal out of the room and butchered it," the insider said of last week's crime.

"This was cruel and professional slaughter."

The insider said that when the tiger's body was found Thursday, the animal's head, legs and skin were missing, the Chinese news agency said.

Xinhua reported that the animal falls under state protection due to its rarity, meaning any suspects would face serious criminal charges.