Firefighters battled a fire McGregor's Jamerican Restaurant at 304 Albany Avenue in Hartford.
People planning to open a supermarket at the site said they think the fire might have been set, but officials said on Monday afternoon that the fire started in a light ballast and the cause was deemed accidental.
Fire officials originally said the fire started in a compressor in the refrigerator around 5 a.m.
McGregor's had been closed for about a month, according to the fire chief.
A man who identified himself as the owner of the business said it was being converted into a supermarket.
He and another man affiliated with the supermarket said on Monday that they thought someone set the fire, but would not say why. Officials later said that was not the case.
The locks on the building were broken on Saturday, the owners said.
Local
Fire investigators told them the locks were working on Monday morning until firefighters broke them to get inside to fight the fire.
Fire officials said the building is badly damaged.
Albany Avenue, Route 44, was closed at Garden Street and Green Street was blocked. Albany Avenue has since reopened.
