The explosion happened just after 4 p.m. and caused the garage to collapse after it caught fire. Charred pieces were strewn across the Orchard Drive property, but the house remained intact.
Relatives and neighbors said the victim was 47-year-old Charles Hallisey and that he was the only person on the property at the time, the Norwich Bulletin and The Day of New London reported Tuesday.
State police would not confirm the victim's identity. Authorities remained at the scene late Monday investigating the cause of the blast.
George Litwin, 75, the father of Hallisey's wife, Beth, said he assumed his son-in-law was working on one of his cars when the garage exploded.
Litwin said Beth Hallisey was on her way to pick up relatives at Bradley International Airport when the explosion occurred. Relatives chose not to call her on her cell phone to tell her what happened.
``I don't want to have to call her. Not now,'' Litwin said. ``Not while she's in her car.''
When she arrived home at about 7:45 p.m., family members, state police and grief counselors were waiting. They kept her and her son, Adam, a Montville High School senior, away from the blast scene.
Dozens of friends and neighbors gathered at the Halliseys.
Hallisey was a supervisor at Electric Boat, Litwin said. He kept a 1966 canary yellow Chevrolet Nova and lawn-care equipment in the garage.
Neighbors said they heard someone in the garage trying to start a car just before the explosion. Some neighbors said they tried to get into the garage but were driven back by the heat.