Tracie Hoffecker says she found the 2-to-3-foot-long (0.9-meter) gator near her home in the Philadelphia suburb of Prospect Park on Sunday morning.
Hoffecker called her cousin, who is a Philadelphia firefighter, and he safely removed the alligator using a net.
Slimy, Scaly, Taily Reptile Rescue arrived on the scene and recovered the animal. Rescue group representative Matt Snider says the alligator will go to an aquarium.
Authorities say the alligator was likely someone's pet and was illegally dumped in the area.
It is legal to own an alligator under Pennsylvania state law. But it is illegal to release them into the wild.
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