The sickening attack on the animal is believed to have happened in the past two weeks.
Mid Sussex Prevention Inspector Darren Taylor said officers were alerted to the property in Haywards Heath on May 11.
He said: “What has been brought to my attention is so shocking and disturbing that even after nearly 20 years in the force it even made me feel ill.
“Sometime in the last two weeks a poor dog was attacked in its own back garden and mutilated by persons unknown.
“This awful and vile event took place in the Bentswood Road area of Haywards Heath.”
The horrific attack on the poor defensive animal was not only photographed – but possibly filmed by the ‘sick individual’, Insp Taylor said.
Officers are now hunting for the video footage which could successfully lead them to finding and prosecuting the perpetrator.
Insp Taylor said: “This footage I gather, has been shared on social media. I ask anyone who may have seen this footage, or even have this footage to come forward.”
He said after speaking to the RSPCA, which visited the property when the alarm was raised by the police, it seems the dog was cut in half with a machete or sword.
“As an animal lover and I have seen some shocking things in my career, I have never seen anything this despicable,” he said.
“This poor animal was cut in half.
“I truly believe that no matter what walk of life you come from, you would find this disturbing and disgusting.”
He continued: “We are appealing to all communities in Mid Sussex here.
“This is a despicable and disgusting act – and we must prosecute who did this. If they can hurt an animal like this, what else are they capable of?”
Anyone who has the video footage or has any information that may help the police is asked to contact Sussex Police on 101, quoting the reference CAC 1010 of 18/5.
Alternatively, they can contact Crimestoppers anonymously on 0800 555 111.
Insp Taylor added: “I think anywhere in the county, or the UK, people are animal lovers. If this happened anywhere in the UK, the outcry would be the same.”
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