OREGON CITY, Ore. -- During a raid of an Oregon City residence Wednesday morning, deputies discovered a dog-breeding operation where animals were living in squalid, unsanitary conditions.

Agents from the Clackamas County Inter-agency Task Force also seized approximately 100,000 Tramadol opioid pills and $7,000 in cash. Natalya Koroteev, Ivan Koroteev, Irina Koroteev and Dmitry Koroteev were arrested at the scene.

More than a dozen puppies and numerous other dogs of varying breeds and ages were found at the residence, located at 16434 South Harding Road in Oregon City. Dogs found at the home included Labrador Retrievers, German Shepherds, Chihuahuas and Cocker Spaniels.

Deputies found dead rats in the puppies' drinking water, in addition to large amounts of dog feces and urine in the pens where the animals were kept, according to the Clackamas County Sheriff's Office.

Investigators on scene said the puppies were living in standing water mixed with urine and feces and that the odor of animal waste was "overwhelming."

"It's appalling," said Sharon Harmon of the Oregon Humane Society. "When you consider how we care for our animals, and we think our dogs should be sleeping in the house if not sleeping in the beds with us, and here these dogs ... are living in a sea of feces and urine."

Promotional materials at the residence said they were breeding "pure AKC registered Black Lab" puppies that came from a "champion bloodline." The promotional materials also said the puppies were kept in a "loving home" and were "always around children."

Agents from the Oregon Humane Society recovered 10 Lab puppies, each 14 weeks old. They also recovered four newborn Chihuahuas, two adult Chihuahuas and one adult German Shepherd.

"From this moment forward, they're safe," Harmon said. "From this moment forward, their lives are immeasurably improved. They'll be fed, groomed, loved, and we'll try hard not to spoil them."

The animals are not available for adoption, Harmon said.

From left to right, top to bottom, Irina Koroteev, Ivan Koroteev, Natalya Koroteev and Dmitry Koroteev.

The four people arrested have been booked into the Clackamas County Jail. Natalya Koroteev is being held for distribution of a controlled substance and bail has been set at $15,000. Ivan Koroteev is being held for a probation warrant. Irina Koroteev is being held for distribution of a controlled substance and tampering with evidence with bail set at $22,500. Dmitry Koroteev is being held on a misdemeanor warrant for failure to appear for driving while suspended. His bail was set at $20,000.

Anyone who may have interacted with the Koroteevs was asked to contact the Sheriff's Office Tip Line at 503-723-4949 or by using the online email form at http://web3.clackamas.us/contact/tip.jsp. If you use the web form, reference CCSO Case No. 16-70352.