Simon, a 7-year-old cat, returned home on the Fourth of July with a gunshot wound in his rear end.
Officials said Wednesday they believe Simon was shot by a high-powered pellet or a small caliber bullet between July 2 and 4.
Veterinarians removed most of the bullet during surgery but it caused a broken femur bone and pelvis.
The bullet also caused extreme pain and Simon suffered some permanent physical impairment of his hind legs.
Simon is stable and recovering at home.
The New York State Humane Association is offering the $1,000 reward for information leading to the arrest and conviction of the person responsible.
"The individual(s) responsible for this heinous assault on a family pet must be brought to justice," NYSHA President Pat Valusek said.
Anyone with information is asked to call the Putnam County SPCA at 845-520-6915.
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