An animal charity known for its years-long investigation into the 'Croydon Cat Killer' has lost three of its members, including founder Boudicca Rising.

South Norwood Animal Rescue (SNARL) was officially set up in 2014 by Boudicca Rising and Tony Jenkins and has attracted international attention since then, including a movie by VICE in which the pair were followed by filmmakers as they investigated the case.

But now a spanner has been thrown in the works following the announcement on Facebook earlier this week that Boudicca would no longer be a part of the operation.

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"It is with deep regret that I announce that Boudicca Rising has formally resigned from both SNARL and the SNARL Investigation Team," a message from Tony on SNARL's Facebook page read.

"This resignation is with immediate effect. She had cited personal and professional differences.

"Some of you will know that she ended our 6.5 year relationship a few months ago. I had hoped we could continue to work together on the investigation however this has proved to be impossible and had led to divisions and arguments amongst us and the wider team. Two other team members have also resigned in her support."

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This isn't the first time that The future of SNARL was put under a spotlight.

In September last year the Met Police closed its case into the supposed Croydon Cat Killer.

in 2015 the Met had launched an investigation into reports from members of the public of mutilated cats, often found with their heads and tails removed, in Croydon and the surrounding area.

But last year police said there was "no evidence" that any of the cats had been killed by a human.

Despite this, SNARL vowed to continue its work, believing that the Cat Killer was still at large.

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Now once again, the charity has vowed to stay strong and continue to move forward with its investigation.

"On behalf of all the victim's owners and all our supporters I would like to extend a heartfelt thank you to Boudicca for her dedication, her tenacity and all the hard work she has put into this investigation over the last 3.5 years," the Facebook post continued.

"We will miss her but she now needs to concentrate on her job and getting her health back. We all wish her the very best for the future.

"We will now regroup and move forward. We are still dedicated to finding the POS killing our pets and the rest of the team are behind me.

"We will continue the search and ask that you continue to support us.

"We will be submitting our charity application in the next week and hope that becoming a registered charity will encourage more people to donate and help us achieve of aim of catching this killer."