A litter of 10 day-old kittens have been found after being dumped in a bin by a school this week, with two cats also found thrown over a wall.
In just 12 hours the kittens and cats were found by Bleakholt Animal Sanctuary of Bleakholt Farm in Bury.
A representative of the sanctuary said: "Bleakholt, just like every local cat rescue, are struggling to cope with the vast numbers of cats needing their help.
"This has been one of the worst years we have known for cats needing our help and we have also seen a vast increase in cats coming to the Sanctuary needing emergency veterinary care.
"Many of the conditions cats are coming into the sanctuary would have been prevented if cats were vaccinated and had basic flea and worming treatment."
Originating in 1957, the Sanctuary at Bleakholt Farm was formed by Olive Lomas who saved a donkey named Maudie from slaughter.
In 1968 Bleakholt became a registered charity, and they now find homes for over 1,300 animals a year.
Jacqui Hill, staff member at Bleakholt Animal Sanctuary, said: "All these poor kittens arrived here as I was on the night shift, if only the people who just abandoned them could see the hard work we do to care for them and the tears we shed for the little babies.
"It took us ages to get the two poor scared little young cats from out of the bushes this morning, if only they just put them in a carrier, we were scared they might run and get on a road, at least they brought them to us so they can now be well looked after."
Bleakholt Animal Sanctuary urges all owners of cats to get them neutered, as there are too many unwanted cats and kittens, and rescues are 'really struggling' to help all that need them.