The Croydon cat killer could be “knee-dropping” their victims to death or smashing them against the wall, according to amateur pet detectives investigating the slayings.

The South Norwood Animal Rescue and Liberty (SNARL) shelter said it had conclusive evidence pets were being slaughtered by blunt force trauma and not mowed down by cars, as previously suspected.

In March the RSPCA claimed scientific analysis of the bodies suggested victims had been run over down before being decapitated.

RELATED: 'Breakthrough' in Croydon cat killer hunt as RSPCA says forensic tests confirm how pets were slayed

But Tony Jenkins, who founded SNARL with partner Boudicca Rising, said: “It has never been cars, there is the slight possibility that the odd case may have been killed by a car and the killer has come back and decided to cut it up.

“But it is blunt force trauma, I think he is either swinging them against a wall, hitting them with club or something, it could be a hard kick or it could be what’s called a knee drop. Basically it is collapsing your body, so you are dropping to your knees on top of a cat.

“Some of them have shown crushes around the abdomen area.”

Two more moggies have been found brutally murdered in Croydon this month, adding to the more than 90 bodies SNARL has collected.

They are feared to be the latest in a string of cats slaughtered since October, prompting a police investigation.

Asked if she had any words for the killer, Ms Rising said: “Give yourself up because we are not stopping until we catch you. You have caused more than enough pain.”

She said the injuries inflicted on the helpless critters had moved on from beheadings, with some cats found chopped clean in half and others missing paws.

Animal rights campaign group Peta and wildlife protection organisation Outpaced have both offered a £5,000 reward for information leading to the arrest of the person dubbed by some the “cat ripper of Croydon”.

Anyone with information is asked to contact SNARL on 07961 030064 or 07957 830490, Detective Sergeant Andy Collin, of the Metropolitan Police, on 0208 6490216, or the RSPCA on 0300 123 8018.