A cat was put to sleep after being shot which damaged her lungs and other organs.
Between 8pm on August 8 and 4.45pm on August 11 it is believed that six year old Fifi was shot with an airgun.
Fifi, who lived with a family in Caishowe Road, Borehamwood, returned home covered in blood on the afternoon of August 11.
The family took Fifi to the vets and it was found she had suffered a gunshot wound which had pierced her lung and other vital organs.
She was also suffering from lead poisoning. The decision was taken to put Fifi to sleep to prevent her suffering further.
Police Constable Rikki Ferraroni said: "This is a cruel crime that has left the devastated owners of this cat forced to make the decision to put their beloved pet to sleep to prevent further suffering."
In July another cat was also shot with a rifle in High Road, in Leavesden.
Anyone with information should contact Hertfordshire Constabulary on 101.
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