The RSPCA is urging members of the public to come forward with information after five cats were poisoned with antifreeze.
The animal charity made the appeal after the deaths occurred in the same town - Melton Mowbray, Leicestershire - over the past fortnight.
Seven-month-old Meereen was the latest victim, leaving her owner Adria Pearce, devastated.
She said: "I haven't been able to stop crying since she died.
"Meereen came home on Friday evening and curled up on the sofa next to me. She seemed to be shivering a little but I didn't think anything was out of the ordinary until the next morning, when I couldn't find her.
"I was out in the street shouting her name. We found her behind the sofa, where she was foaming from the mouth and trying to be sick.
"I knew something was desperately wrong so I took her straight to the vets, where tests confirmed that she had ingested antifreeze.
"We'd hoped she'd be able to be saved, but sadly she passed away three days later."
The RSPCA said three cats in the same area have also died from antifreeze poisoning in the last seven days, while another cat died after ingesting a toxic substance two weeks ago.
Anyone with information is asked to call the RSPCAon 0300 123 8018.