ST. CLOUD, Minn. (AP) ’ Authorities say they believe animal rights activists set free from a pelt farm in central Minnesota 35,000 mink incapable of surviving in the wild.

Someone dismantled parts of the exterior fence at Lang Farms near Eden Valley late Sunday or early Monday and released about 35,000 mink from their cages, according to the Stearns County Sheriff’s Office. Eden Valley is about 75 miles (120 kilometers) northwest of Minneapolis.

Sheriff Don Gudmundson said Tuesday he believes members of an animal rights group released the mink, but didn’t steal any of the animals, together worth $750,000.

“It’s pretty hard to steal 30,000 to 40,000 mink. What are you going to do put them in a trunk? They’d chew your fingers off,” Gudmundson said.

Hundreds of mink have already been found dead in the area of the farm, the sheriff said.

“If they (perpetrators) actually cared about animals they wouldn’t release thousands of mink to die out in the heat. We’ve already got reports of chickens killed. Don’t they care about God’s chickens? Gudmundson said.

The mink don’t know where to go because they’ve never been out of their cages, authorities said. The FBI is assisting in the investigation.

Gudmundson said the farm doesn’t have surveillance video. The Tri-County CrimeStoppers group is offering a $1,000 reward for information leading to the vandals.