Nearly 170 dogs were rescued Monday from a rural property in Worth County, near the Minnesota border in northern Iowa.

After a monthslong investigation, county authorities executed a search warrant early Monday at a commercial breeder known as White Fire Kennel. The American Society for the Prevention of Cruelty to Animals (ASPCA) called the operation a "puppy mill."

The dogs — all Samoyeds — were found inside a home and in barn-like structures, said Tim Rickey, vice president of ASPCA Field Investigations and Response. Kennels meant for one animal were overcrowded with eight or nine dogs, he said.

Ranging in age from young puppies to 9 years old, the dogs were living in "appalling and overcrowded conditions and exhibiting signs of neglect with no access to clean water," ASPCA said in a statement.

Four cats also exhibiting signs of neglect were found inside the residence.

In Manly, the temperatures dipped into the teens, with snow, for most of the day.

"Many of the dogs were found in filthy, dilapidated kennels in below-freezing temperatures with minimal protection from the elements," the ASPCA said in its statement. "There is debris scattered throughout the property as responders work to safely remove fearful and under-socialized dogs."

Rickey, who arrived there around 7 a.m., called it a "hectic environment."

About 30 animal welfare workers and law enforcement officers were still at the property on Monday afternoon. Rickey said he expected they will be there late into the night.

Worth County Sheriff Dan Fank said law enforcement has previously "tried to work with the individual in addressing the growing concerns about the welfare of her animals over the past several months and, unfortunately, met resistance.”

Monday afternoon, Fank said the breeding operation is still an "active scene." Criminal charges are pending against the owner, he said, whom he identified as awoman living alone.

Online profiles said White Fire Kennel is owned by Barb Kavars of Manly.

Fank said the sheriff's office asked the ASPCA and other animal welfare organizations to assist in removing the dogs and getting them care and treatment. The dogs and cats are being cared for at temporary shelter, the ASPCA said.

Rickey said medical experts are evaluating each animal at the property and will again when they're transported to the shelter. None of them were critically injured, to his knowledge, he said.

The investigation began several months ago, when local animal welfare groups became aware of conditions at the home and alerted local authorities.

Kavars was previously licensed through the USDA, according to the ASPCA. Fank said the property is at 1071 Highway 9, in Manly.

More:Iowa has some of the nation's worst puppy mills. But the federal government is hiding their identities.

More:These 10 Iowa puppy mills were among the worst in the nation, according to the Humane Society of the U.S.

“This is a major breeding operation, and it is a very unsanitary environment," Rickey said. "The dogs were competing for resources like food and water, and because of the overcrowding, were much more likely to be involved in fights. That type of environment is not acceptable."

Iowa has long been home to some of the worst commercial breeders in the nation. This year, Iowa has 10 breeders on the Humane Society of the United States’ “Horrible Hundred” list, an annual compendium deemed the worst in the country by the nonprofit.

More:Looking to buy a dog? Here's how to make sure you're buying from a responsible breeder, and not a puppy mill

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