By Mark Hughes, New York
1:16PM BST 26 Jul 2012
The apparent 'monster' was found and pictured by an amateur photographer who was walking under the Brooklyn Bridge in Manhattan on Sunday.
The lady who captured the images, Denise Ginley said: "We were horrified by it and we took some camera phone pictures and then finally we decided to come back with my camera and I got up the courage to climb over the fence and get closer to it."
On first glance it appears that the animal is simply a bloated pig – a theory the New York Parks Department insist is correct – but closer inspection reveals that the animal appears to have toes rather than hooves.
Online theorists speculated it may be a dog or, even more worrying, a giant rat. Other online comments suggest it could be an aardvark, a raccoon or something related to a possum.
One online commentator suggested the beast was from a nearby government-run animal disease centre.