MONTEREY (AP) — A mother and daughter were charged Thursday in connection with an animal hoarding case after authorities recovered 51 neglected cats from their coastal California house and discovered 113 dead kittens in a nearby apartment.

Donna Johnson, 46, faces three felony animal cruelty charges, and she and her mother, 79-year-old Maggie Johnson, face three misdemeanor neglect charges.

Seaside police and the Society for the Prevention of Cruelty to Animals for Monterey County discovered the animals July 24 while conducting two searches. They investigated after a property manager alerted them about potential hoarding.

SPCA Sgt. Stacy Sanders, the lead investigator, said authorities discovered 113 dead newborn kittens in an apartment where Donna Johnson had been living on and off.

Authorities followed a tip that more cats were moved to a nearby house owned by Maggie Johnson. There, they found 51 adult cats who were alive, but sick and neglected.

"The cats were living in extremely horrible conditions," Sanders told the Associated Press in July. "They were separated into two groups and locked into rooms with little to no ventilation. The floors were saturated in urine and feces."

The Johnsons told investigators that those cats had given birth to the kittens who were found dead, Sanders said.

Deputy District Attorney Marie Aronson said the Johnsons were not charged for the kittens' deaths because investigators could not conclude the causes.

"We weren't able to make a good forensic opinion about why these kittens died or what their cause of death was," Sanders said. "They were too decomposed."

The surviving cats were taken to the SPCA for Monterey County shelter where they received medical attention and care. SPCA spokeswoman Beth Brookhouser said most of those animals had respiratory infections, parasites and broken teeth. Later, two were euthanized because of illness and one died for unknown reasons.

Officials say most of the cats are recovering and in good spirits. The SPCA of Monterey County has reported getting hundreds of calls and photos of missing cats in hopes that they are among the rescued animals.

"We even had people from back East call us desperately seeking a loved animal," Sanders said.

Following international attention, the animal welfare group received an outpouring of support including $8000, $4100 in merchandise and several offers to adopt the cats.

The cats will not be available for adoption until the Johnsons' case concludes because they are considered evidence, officials said.

Authorities said the Johnsons were not arrested or in custody but would not elaborate. It was unclear whether the Johnsons have legal representation.

A message left for a number listed for Donna Johnson was not immediately returned Wednesday.

The women are expected to appear in court Sept. 11. Donna Johnson faces a maximum of three years in jail for each felony charge, and both Johnsons face six months for each misdemeanor.