QUEBEC -- Firefighters wearing special equipment have removed a man and a woman from their Quebec City home after finding about 30 cats in the residence.

They say excrement and urine stains were visible in the dwelling and that there was also a strong concentration of ammonia.

The residents, who are believed to be in their 50s, were taken to hospital on Tuesday to undergo health tests.

A spokesman for the Quebec City fire service described a scene of extreme insalubrity.

The cats were still in the house as of this morning as authorities continued to ventilate it to enable animal-welfare officials to enter.