The 10-year-old flagged down a police officer in Bridgeport because he reportedly saw an adult male throw a box over the bridge into the water at Berkshire and Knowlton, said Bridgeport Animal Control.
The boy reportedly heard meowing from a box fully taped and tied in a trash bag, according to the shelter.
He then ran to the edge of the water and rescued the cat, a male.
The male cat "appears to be OK, just timid right now," said animal center.
Animal Control asks that anyone with information about who might have been involved in the alleged incident to call 203-576-7727.
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