The Mayday call went out around 12:45 p.m. for a vessel that was going down somewhere in Milford Harbor, fire officials said. Milford Marine Units and the US Coast Guard responded.
A quick-thinking oyster boat captain, having heard the distress call, went to the area and found the craft completely submerged with the three boaters in the frigid waters about two miles offshore, Milford Fire Department said. They pulled them out and began to take them back to shore.
Responders caught up with the oyster boat as it was returning to shore and transferred the three to a fire department vessel. They were taken to Milford Hospital for evaluation, with one boater in critical condition.
Their names and information were not immediately available.
Authorities are investigating what caused the boat to sink.
This is the second time this fall that an oyster boat has rescued fellow boaters.
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