Authorities say officers responded to a boat explosion around 3:20 p.m. at the Raritan Marina, located at 1707 Rt. 35 in Laurence Harbor in Old Bridge.
The explosion launched a 57-year-old resident into the water. He was pulled out by bystanders.
He suffered burns to his face and legs and was airlifted to Robert Wood Johnson University Hospital, New Brunswick for treatment.
A 47-year-old South Amboy resident suffered blast injuries from glass to his stomach and arms. He was taken to Bayshore Medical Center for treatment.
First responders, including police, fire and EMS crews, quickly arrived at the scene to aid the injured and secure the area.
New York City Fire Department marine teams also responded and helped local fire departments.
The charred-out boat eventually sank from the weight of the water as fire crews put out the flames.
The cause of the explosion is under investigation, but officials say the incident does not appear to be suspicious.
The marina is closed due to the investigation.