Shocked cat owners found their pets bleeding on their doorsteps during a spree of attacks in Brighton, a court has heard.
One woman said: "I immediately thought it was a stab wound."
In a statement read out in court, she described how blood "splurted out" from her 11-year-old cat Gideon.
He eventually recovered from the three-quarter inch wound, she told the court, and vet's bills for his surgery came to more than £1,600.
Shopping centre security guard Steve Bouquet is accused of killing nine cats and injuring seven more in the East Sussex city.
The attacks left detectives puzzled for months until a cat owner's CCTV appeared to capture an attack, prosecutors say.
Bouquet, 54, from Brighton, is standing trial after pleading not guilty to 16 counts of criminal damage in relation to cats and one count of possession of a knife.
On Wednesday, jurors at Chichester Crown Court were told how owners of several cats realised their pets had been injured.
Carolyn Green found her short-haired tabby Tommy lying on her doorstep, clearly injured, after only being let out about 15 minutes before.
"I picked Tommy up and noticed blood on my T-shirt," Ms Green said in a statement read out by the prosecution, describing how she then took him to the vet for treatment.
"The vet called and reported that Tommy had been stabbed - I was shocked."
Tommy had suffered a 4cm cut, the vet discovered, and did not survive his injury.
Penny Vessey told the court her black and white cat Rigby was "always incredibly friendly" and liked to lie outside the house so people could stroke her.
But that stopped after Rigby was injured on Halloween night in 2018, she said.
While Rigby made a physical recovery from her injury, Ms Vessey said it was not until very recently that she has started engaging with people again.
On Monday, jurors heard that after Bouquet was arrested on 2 June 2019, officers searched his house and found a knife in the kitchen area.
His DNA was found on the handle and domestic cat DNA was found on the blade, the court heard.
The trial continues.
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