A pair of thieves are posing as animal control officers and stealing purebred dogs from people's backyards in southern Illinois.

Five dogs have been stolen in three different counties, Perry County Sheriff Steve Bareis said. At least twice, homeowners scared off the thieves but they will continue until they are caught, he said.

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"They've been taken out of fenced areas and so forth. They're basically patrolling during the day for them and they seem to be coming back at night or making sure people are gone and taking them at that time," Bareis told WITI.

Bareis said the dogs that were stolen are likely gone for good, sold for up to $1,000.

"It's scary, but I always tell people you cannot leave your dog unattended," Amber Gulley, with the Perry County Humane Society, told WITI.