Police say the boy fell in the Housatonic River in Stratford while walking on the Birdseye Street Boat Ramp around 1:30 p.m.
Crews searching for missing 6-year-old boy who fell in river in Stratford, Connecticut
The exact circumstances are still under investigation, but the child's mother was with him at the time.
A United Illuminating employee jumped into the river in an attempt to save him, but the boy has not been found.
A full-scale search began, involving the Coast Guard and local first responders.
The launch is located at the mouth of the river just before it feeds into the Long Island Sound, making for difficult dive conditions.
By noon on Thursday, boats finished searching the areas identified by Coast Guard computer modeling as the likeliest locations where the body might be found. Divers remained in the water until the currents became too strong.
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