The body of a cat was found washed up on a beach in a picnic basket.
The RSPCA is now appealing for information after the discovery on Caister beach on Wednesday night.
The picnic basket was found by members of the public, who opened it up and discovered the dead cat inside.
They contacted the RSPCA, who have now launched an investigation into the death.
The cat is thought to be a young adult, black and white in colour, and was wearing a black collar with diamante studs.
The wicker picnic basket was lined with red gingham check material.
MORE: Body of dead dog found in river tied to concrete weightA post mortem examination is due to be carried out on the cat's body, but it is not believed to have been in the water for a very long time.
This is the second animal body which has been found in water in the past two days.
The RSPCA is also investigating what is believed to be an unrelated incident where the body of a dog was found in the River Thurne at Potter Heigham on the afternoon of Tuesday, June 13.
The German Shepherd was wearing a metal choker collar, which was clipped to a short lead which was attached to rope tied to a concrete mud weight.
RSPCA deputy chief inspector Ben Kirby, who is investigating both incidents said he did not believe the two incidents were connected.
He added: 'It is just awful that we have had two dead animals in a spate of two days.
'We will be carrying out a post mortem examination to establish the cause of death, and this time I am keeping an open mind as to whether the cat was alive when it was in the water.'
Mr Kirby said if the pet was alive when it was put in the basket, then it was a truly terrible way to treat an animal.
The inspector added: 'I am urging anyone who may know who the owner of this cat is, or who has any information or may have seen someone acting suspiciously in the area that day to contact me in confidence on the RSPCA inspector appeal line on 0300 123 8018.'
To report a case of animal cruelty, you can call the 24-hour a day RSPCA hotline on 0300 1234 999 to report cruelty or an animal in distress.
The call will cost the same as any call to a normal UK landline number.
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