SKAGIT COUNTY, Wash. -- Prosecutors have filed additional charges against the couple accused of operating a puppy mill in Mount Vernon.

Richard and Marjorie Sundberg now each face four counts of animal cruelty in the first degree, four counts of animal cruelty in the second degree and one count of transporting or confining in an unsafe manner.

The couple is due in court on Feb. 27 to enter pleas on these new charges.

Nearly 450 dogs were rescued from the Sundbergs' Mount Vernon kennel where animal control officers found the animals living in deplorable conditions.

Detectives said the dogs were kept in tight cages contaminated with feces and urine that sat alongside bodies of dead dogs in unheated spaces.

Many dogs had been left without any food or water. Veterinarians later determined some of dogs were suffering from coccidia, an intestinal disease, and many others were pregnant.

The prosecutor isn't relying on charges alone; he hopes to put the Sundbergs' Mountain View Kennel out of business.

The county commissioner passed a special resolution last month, giving the prosecutor authority to sue the dog breeding operation for creating a public nuisance. If a judge agrees to the allegations, the Sundbergs would never be able to own a breeding business in Skagit County again.

Investigators first learned of the Sundbergs' operation after serving search warrants at the homes of their daughters, Renee Roske and Mary Anne Holleman in Snohomish County.

At one of the homes, deputies found "several hidden compartments built into the house to hide dogs," court documents state. Thirty nine dogs were found in the two homes; however, none of those dogs were seized.

At Holleman's kennel in Gold Bar, deputies found 155 dogs, 87 of them of them stashed in an attic, living in ghastly conditions so horrific that it shocked even veteran animal control officers, investigators said.

Officers said the odor from the feces and urine was so overpowering it could be detected well outside the residence. A large commercial dumpster stood in the yard overflowing with dog waste.

Medications and used syringes, used to treat sick animals, were found scattered in front of pens and in a refrigerator.

Investigators seized all the dogs from the property, as well as four cats and three parrots.