A furious mum says her family cat of nine years was killed on the same day he consumed poison.

Kirstin Blanchard, 42, said her husband found Eli lying on the grass at their Beckenham home last Wednesday on Copers Cope Road before being rushed to hospital.

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Unfortunately, Eli died while on the x-ray table – and blood tests revealed "extremely high levels" of phosphorus in his system.

"The phosphorous levels were as high as the machine could read," Kirstin told News Shopper.

"I hope the scumbag who did this suffers some day themselves."

Kirstin is convinced the poison was left deliberately to hurt either rodents or foxes.

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She shared the news on social media to warn other pet owners about the danger.

"It was shock really, absolutely shock," Kirsten recalled. "I feel more anger than anything. I am very against harming.

"I am very sad obviously. You don't think someone would actually do it. It looks a little too suspicious."

She went on: "If you are putting poison down take into consideration other people’s domestic animals like cats or dogs."

Kirstin said they have another family cat who grew up with Eli and has been "depressed himself" since he died.

The concerned mum added: "We wish to urge the residents of Beckenham to be vigilant with their animals."