The sighting took place in Suffolk County in the area of Boulevard Avenue in West Islip around 10:40 a.m., Tuesday, July 26.
Police responded to the area and the animal was not located, said the Suffolk County Police.
John Di Leonardo, an anthrozoologist and president of Humane Long Island said the animal is most likely a lynx hybrid that was someone's pet and was abandoned.
"These are wild animals and not pets," said Di Leonardo. "Hopefully the animal can be caught and rehabilitated and placed in a responsible wildlife habitat."
The cat (pictured) looks unhealthy and undernourished, he added.
"I can't stress enough that people need to realize that these exotic animals are not pets," Di Leonardo said. "This one most likely escaped or was released by the 'seedy' person that owned it."
Carole Baskin, of "Tiger King" fame, commented on the animal after Di Leonardo posted its picture on Facebook.
"The poor thing looks emaciated," she wrote.
If anyone sees the animal they are asked to call 911 or the non-emergency police number, 631-852-COPS. They are also asked to contact Di Leonardo at Humane Long Island at 516-592-3722.
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