It happened Saturday, Aug. 5 at about 6 p.m. in Stony Brook.
A 54-year-old East Setauket man was operating his boat, a 2003 Sea Ray Sundancer, in Smithtown Bay, traveling from Sunken Meadow State Park to Stony Brook Marina, when it stalled, Suffolk County Police said.
An explosion occurred on the boat a short time after it was restarted.
A 53-year-old woman, the wife of the boat operator, and a passenger on the boat, was transported to Stony Brook University Hospital for the treatment of serious injuries.
Another passenger, a 58-year-old Holbrook man, was transported to the same hospital for treatment of minor injuries.
The boat operator and another passenger on the boat were not injured.
The cause of the explosion is under investigation, but it does not appear to be suspicious, said police.
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