Ontario's animal welfare organization says a hoarding issue may have contributed to a situation at an abandoned rural property where local rescue groups say they've found dozens of cats, dead and alive.

Rescue groups say they have found 153 dead cats and four dead dogs, as well as more than 100 living animals in varying levels of health, in a property in Beamsville, Ont., in the Niagara Region.

The Ontario Society for the Prevention of Cruelty to Animals said it is in the midst of an animal cruelty probe, which began in December, working with a woman who they said used to rent the home on the property.

No charges have yet been laid.

"It did appear to be a hoarding situation," spokeswoman Alison Cross said Monday. "We were there, feeding animals, going back daily, addressing any concerns of animals that might have been appearing — they are roaming outside, so it's not easy to find them all."

The woman who lived on the property may also have been collecting dead animals "from roadkill and other things," and putting them in barrels that have been found at the site, Cross said.

Local animal rescue organizations recently became involved in efforts to care for cats found alive on the property.

Pam Huson, who runs the Beamsville 4Paw Rescue, said the animal control organization in the area asked her and several other rescue groups on July 19 for help dealing with the situation.

"It was a nightmare," she said, noting that cats had overrun the property.

Saved about 100 cats

Huson said her organization saved about 70 cats from the site and another group, Project Save A Cat's Life, said it rescued about 30 cats.

The groups also found dozens of dead felines, Huson said.

The dead cats were found inside the home near windows and doors, which were riddled with scratch marks, Huson said.

"The stench was so awful that we were throwing up," Huson said.

The residence where the cats and dogs were found was on Merritt Road in Beamsville, Ont. (Google)

Dead cats found packed in rain barrels

The groups also found the bodies of dead cats inside rain barrels on the property, Huson said.

"We followed the flies and the maggots and the birds and the stench and that led us to the barrels," she said. "It was shocking."

In all, Huson said rescue groups have counted 153 dead cats and four dead dogs found on the property so far.

The OSPCA said it was concerned that the rescue groups may have tampered with evidence in its investigation.

"We recognize the passion behind the rescue groups wanting to help the animals, but when it comes to an investigation there is a process that has to be followed, or else you can jeopardize the investigation," Cross said.

She said the OSPCA was still waiting for evidence from the rescue groups on the number of cats, alive and dead, found at the site.

However, Huson said that she has offered all of her evidence from the property, from photographs to veterinary reports to her own accounts, to OSPCA investigators who handling the case.

The cats that have been rescued from the property are doing well after being treated for a variety of illnesses and injuries, she said, and are healing in foster homes.

"They're happy, they're cuddly," she said. "After the long weekend, we're going to have an adopt-a-thon."