Pet owners in West Sussex say they are living in fear amid reports that 19 cats have been killed and mutilated after being snatched.
In some attacks cats have had heads, legs and tails cut off
Sussex Police say they are taking seriously reports that 19 cats, along with four rabbits and a fox, have been found dead in 10 months.
In some attacks, in towns including Burgess Hill and Haywards Heath, cats have had heads, tails or legs cut off.
A police spokesman said he thought more than one suspect was involved.
In one of the latest incidents, a teenage girl said she saw a man grab a cat in Chichester.
When she confronted him, he dropped the animal and ran off.
Attacks on pet cats have also been reported in Rustington, Angmering, Littlehampton and Portslade.
The reports are being collated by pet detective June Bailey, who lives in Rustington.
She told BBC News Online that lots of people had been reporting attacks on their animals.
She said: "We are all living in fear - it's like playing Russian roulette."
She said in one incident, a cat's head was discovered buried in a flowerpot, while a decapitated animal was found in a carrier bag with two dead rabbits.
Another cat, a British blue, had both its head and tail cut off, and was reportedly dumped over a wall with a decapitated fox.
Mrs Bailey said all the attacks had happened between midnight and 0300 BST.
Trevor Weekes, of the East Sussex Wildlife Rescue and Ambulance Service, said the cases were not consistent with fox attacks.
"The chances of a wild animal being responsible are pretty remote," he told BBC News Online.
Insp Kim Hudson, of Sussex Police, said: "The incidents have been very distressing to owners and we want them to know that we are concerned about the animals' deaths.
"We are reviewing the allegations, however we do not believe they are all linked to one individual."
He said police were keen to hear information from anyone whose cat had died in strange circumstances other than road accidents.