A malnourished cat had to be put to sleep after it and eight others were dumped at a Cavan animal sanctuary.
Last week, while the Kitten Cottage in Virginia was closed, a woman was caught on CCTV dropping off two boxes of kittens and adult cats.
When staff returned, they found the animals to be very friendly but starved.
One was so sick that despite days of treatment at the vets, it had to be put down.
Days later, three seven-week-old kittens were found dumped close to a lake and in a similar condition.
Máire Egan from the Kitten Cottage said that in her 24 years of working with animals, she's never seen anything like it.