There were 6,901 animal cruelty cases investigated in the region last year, new figures show, including a cat whose legs were crushed.
The RSPCA listed Norfolk as the fourth highest in the south east for animal welfare complaints in 2015.
Statistics released today by the charity show there were 2,689 cases in Norfolk, compared to 2,351 in Cambridgeshire and 1,861 in Suffolk.
They included a case about a kitten found in a Norwich garden with its back legs crushed, having been swung around by its tail.
The cat was found collapsed and injured in a Norwich garden. Buster, an eight-month-old ginger and white tom cat, was discovered by his owner after she heard meowing coming from a nearby garden.
He was discovered slumped on the floor and unable to move one evening in March last year.
Buster's owner at first thought he had been involved in a road traffic accident, but a vet said his injuries were consistent with having been deliberately squeezed, battered and swung around by his tail.
While being treated a hand print was discovered on his skin like he had been squeezed with a lot of pressure.
His back legs were also 'smashed' and his tail was badly broken.
The injuries were so severe that it is thought that Buster was left in the garden as he wouldn't have been able to have got there on his own.
Buster was operated on and his tail was also removed because it was dislocated.
RSPCA Inspector Ben Kirby said: 'This was a despicable attack on a little kitten and would have caused great suffering. Whatever happened it must have been extremely frightening for the kitten and upsetting for the owners - Buster is lucky to be alive.'
RSPCA chief superintendent for London and the south east Insp Paul Stilgoe said: 'This year has seen some of the most distressing cases our inspectors have ever come across – and in so many cases the victims were dogs.
'The level of cruelty, neglect and abuse we see across the region on a daily basis is heartbreaking but thanks to the help of members of the public we have been able to make it a bit safer for these animals.'
Greater London was named as having the highest number of animal welfare complaints in the country, with 11,050 investigated last year. In the south east it was followed by Kent, with 5,305, and Essex with 4,641
The RSPCA said this year had seen some of the most harrowing cases, including a chihuahua that was stolen, fed drugs and tortured in Kent. The charity said dogs were the most persecuted pet in the south east.
Dermot Murphy, assistant director for the inspectorate, said: 'The stories in this report show a snapshot of the horrific level of cruelty we have seen in the last year, which have to be some the most extreme cases I have ever heard of.'
Do you have an animal cruelty story? Call Luke Powell on 01603 772684
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