Dozens of cats have been seized from a home in St. Hubert, and many are in such poor health they will have to be euthanized.

The owner of the home had given up living inside the building some time ago.

The cats had caused so much damage, and the smell from their feces and urine was so strong, that he bought an RV so he could have a place to live.

Authorities learned of the rampant cats from the owner of the home.

Earlier this week the man had a stroke and called a neighbour for help.

That neighbour made sure he got to hospital for treatment, and from his hospital bed the man told authorities that someone would need to take care of the dozens of cats living in his house.

When police arrived at the home on Legault St. on Thursday morning, the smell of ammonia was so strong they could not go inside.

"The smell was so bad they immediately closed it and saw from the window there were dozens of cats inside," said Michel Hugerot of the Longueuil fire department.

They called for backup, and hazardous materials gear, because it was to dangerous to go in.

"When there is a lot of excrement., it decomposes and produces ammonia, a very dangerous gas," said Hugerot.

After airing out the house for several hours police and South Shore Animal Services (Services Animaliers de la Rive Sud) removed the cats from the home.

Didier Molard said many of the cats are quite ill.

"We'll determine the health of the cats. Unfortunately many are in poor health and will have to be put down and so will those who could potentially infect other cats," said Molard.

Linda Robertson of the SPCA Monteregie said incidents such as this are extreme, but point out the need to spay and neuter pets.

"Unless we have an effective sterilization program we're never going to come above this problem. In many other provinces they have mobile clinics to go through various towns and sterilize stray animals but so far we haven't been successful in getting one here in Quebec," said Robertson.

There is a possibility the owner of the cats could face charges for animal cruelty and other municipal bylaw violations, but right now police say they are more concerned about the man's health.