Horry County authorities say they have euthanized more than 100 of the cats seized at a private shelter earlier this week.
Officials had seized 237 cats from the no-kill Sacred Vision Animal Sanctuary in Myrtle Beach after a magistrate ordered their removal Tuesday.
A veterinarian put down 107 cats. County spokeswoman Lisa Bourcier says the animals suffered from a variety of ailments, including herpes, ringworm, maggots, gum disease, tumors and other problems.
The county is treating 101 cats for problems such as infection, hair loss and being underweight.
Twenty-nine others were returned to sanctuary owner Elizabeth Owen. She had been charged with improper care and treatment of animals in September. She told a magistrate earlier this week the animals were being cared for properly.