Fairfax County police said yesterday that they will ask a judge Monday to declare an 82-year-old woman who hoarded 488 cats an unfit pet owner and prohibit her from owning animals.

This week, police removed the cats, many of them dead, from Ruth Knueven's home on Ludgate Drive in Mount Vernon and from her daughter's townhouse on Lakepointe Drive in Burke. It was the second time since 2001 that police have taken more than 100 felines from her.

Police said the court action to declare Knueven unfit is the next step in preventing her from continuing to hoard animals. Police said they will ask the judge to order a mental evaluation for Knueven and will seek a court order allowing them to conduct periodic follow-ups to make sure more cats aren't gathering.

"Our concern is how do we prevent [a recurrence] weeks and months down the road," said Mike Lucas, the county's senior animal control officer. Lucas said it is not unusual for those who have been deemed unfit to wind up in court again.

Meanwhile, police said yesterday that they seized 43 cats Thursday from a home on Lorfax Road in Lorton. Police charged Margaret Gaffney, 71, and Walter Gaffney, 40, with failing to care for their animals.

In the Mount Vernon case, Knueven has been charged with two counts of failing to care for her animals as well as a charge of failing to properly dispose of cats found in her home.

Knueven also faces a charge of obstructing justice, police said, because she tampered with traps that animal control officers had set to round up the feral cats still hiding in her home, and one of cruelty to animals, stemming from the death of one of the cats.

Police were summoned to Knueven's home July 8 when neighbors complained of a noxious odor. According to court records, Knueven was reluctant to surrender her cats, working in concert with her daughter, Karen Forrest, 57, to hide them as investigators were combing her home.

Police returned to her home July 11 to check the traps they had set and found them empty. Drawn to meowing in the back yard, investigators found seven cat carriers crammed with 33 cats -- one of them dead -- hidden in the bushes. They believed Knueven was attempting to hide the animals from police and accidentally killed one.

Police cited Knueven's resistance to give up the animals as the reason for searching Forrest's townhouse Wednesday night. Inside they found 38 adult cats, nine kittens and 134 dead felines. Police said they have expanded their investigation to include Forrest.

Like Knueven's home, Forrest's townhouse sustained extensive animal damage to the floors, walls and plumbing and was largely coated in animal waste. The Burke home has also been declared unfit for habitation until extensive repairs are made at a cost of many thousands of dollars, officials said.

The damage appeared to have been sustained over a long period of time, leading police to conclude that Knueven was using the Burke townhouse as a second location where she kept her growing clutter of feral cats.

Police have recovered an additional cat from inside the townhouse and have set traps both inside and out to round up stragglers. Nearly all the cats were undomesticated and suffered from contagious respiratory problems, officials said. All but eight were euthanized.

In an interview Wednesday, just hours before her daughter's townhouse was raided, Knueven said the blame for her collection of cats fell squarely on her own shoulders, explaining the problem "mushroomed" over a period of years.

She said she started taking in the cats to stanch a problem with strays created by a neighbor who leaves cat food in his open garage. She said that she was trying to protect them and that her efforts got out of hand as the cats began to multiply.

"I'm glad the nightmare is over," she said.