DENVER -- Customers and former employees say Jessie's Pet Paradise in Castle Rock sold sick puppies, an accusation that state inspectors agree with.

Jill Koehler bought two Pomeranian puppies from the Jessie's Pet Paradise over Labor Day weekend. Within hours of buying the puppies she had to take them to the emergency room, she said.

"She was paddling her little legs and her teeth were bared. She was just in this frozen state," Koehler said.

One dog, Mia, was having constant, uncontrollable seizures.

"I didn't want her to go through the night in that condition. I just thought we should put her down," Koehler said tearfully. "It's horrible. Something you thought was going to be fun ends up being a horrible nightmare."

Mia's sister, Pippin, a tiny black Pomeranian, was diagnosed with pneumonia and has recently finished taking antibiotics. Vets tell Koehler Pippin will recover.

Besides the emotional toll, the sick dogs have also cost Koehler monetarily.

"The vet bill has come up to over $1,600 for the two puppies," Koehler said.

Several customers and former employees have contacted Call7 with complaints as disturbing as Koehler's.

Meilon Dizmang said, after buying a puppy from Jessie's Pet Paradies a year ago, "The vet said this animal was severely dehydrated, she should not have been sold."

Former employee, Michelle Burhenn admitted, "I knew half the time the puppies we were selling were sick."

Ruth Lee told Call7 about the two puppies she purchased from Jessie's Pet Paradise in October.

"There's a possibility they could have Parvo," Lee said.

Lee, who happens to be a pediatric nurse, gives her puppies IV fluids daily to keep them hydrated and hopes they will eventually recover. Vets could not give Lee a clear diagnosis and she said she could not afford overnight hospital care for her dogs. Lee said she demanded a refund from Jessie's Pet Paradise, but a store employee told her no.

Call7 contacted Jessie's owner, Tracey Stillwell, who declined to go on camera. She said she was being targeted by "bunny-squeezing, tree-hugging, slimeball animal activists."

"When dogs get out of our care we have no way to control what happens to them," Stillwell told Call7.

Stillwell also said state inspectors found, "No dogs that had a problem."

But Dr. Kate Anderson said that is not true. Anderson heads the Pet Animal Care Facilities Program, a division of the Department of Agriculture that licenses and inspects pet facilities.

"I found seven dogs that needed to go to the veterinarian the next day," Anderson said. "It's very serious. We have high concern for the animals in the store."

Call7 was there in late October when Anderson personally inspected Jessie's Pet Paradise after receiving more than a dozen complaints about the store over a seven-month period.

The Department of Agriculture recommended a one-day closure on that visit, when inspectors discovered a potentially deadly Parvo outbreak and no appropriate isolation area for sick puppies.

"They have failed inspections. They have civil penalties. They are currently under a cease and desist order," Anderson said.

That order means no new dogs can be delivered to the store.

Department of Agriculture documents show several "critical" and "repeat violations" involving "cleaning and sanitation," not providing veterinary care and a lack of recordkeeping.

The results so far means $250 in fines and a possible revocation of Stillwell's license.

When asked if all the violations could lead to a puppy's death, Anderson responded, "It's possible, yes. Some of those puppies may still die."

Call7 went back to the store undercover to see if conditions had improved.

When asked about the puppies, an employee said, "The one that's at the vet right now has pneumonia. He's on medication. The one I took to the vet last night, after what they did to him, you can tell he's feeling much better."

The employee said Jessie's Pet Paradise is having a sale and hopes to sell all the remaining puppies by Nov. 16 because the owner has decided to close.

"The Italian greyhounds are $375 and we'll throw in a second for $100," the employee said in the undercover video.

Anderson said her agency is still investigating the store, but if Jessie's Pet Paradise closes, that would end the process. Stillwell could reopen under a new license at a new location with a clean slate.

Koehler hopes the store never gets another chance.

"I want these people stopped. If we stop purchasing dogs from these places then they eventually can't make it and I want them stopped," she said.

The Castle Rock Police Department said it is also investigating Jessie's Pet Paradise and that they are looking at possible criminal charges against Stillwell. Anderson said if Stillwell is charged, that could prevent her from getting a new license.

Authorities suggest that you do your homework before you buy a puppy. Get a checklist of do's and don'ts of getting a dog.

If you have concerns about the health or care of pet animals in a licensed facility you can file a complaint with the Colorado Department of Agriculture, Pet Animal Care Facilities Program (PACFA) online or by phone at (303) 239-4167.