The department's Randy Babb said complaints from neighbors led to the discovery of a juvenile orange tiger tied up with a collar in a Phoenix back yard and a white tiger kept in a dog kennel in Gilbert, KPHO-TV, Phoenix, reported Tuesday.
Babb said the tigers were likely legally purchased in another state, but are not legal pets in Arizona.
"These animals want space to roam in and any kind of enclosure that you can provide in a back yard will be insufficient," Babb said. "You never know when something is going to turn, and when it does, when the animal is large like this and is a very powerful, very efficient predator, it can get ugly very quickly."
Babb said both tigers appear to be in good health. He said authorities had not yet located the owner.