Exterminator Mike McClay told officers on Tuesday he got the alligator while on the job in West Philadelphia about three and a half years ago. At the time the 'gator was about 18 inches long.
He said the owner's mother told him her son was in jail and she was trying to get rid of the reptile.
McClay built a cage, with a heated pool, and a light for the alligator to sun himself.
The alligator was taken to a barn at the Pennsylvania Society for the Prevention of Cruelty to Animals and is scheduled to be shipped to a wildlife refuge on Wednesday.
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