Investigators said Thursday that an electrical short started the blaze that gutted a block of Greenville Avenue earlier this week.
The massive fire ripped through several businesses, including Terilli's Restaurant & Bar, Mick's Pub, the Hurricane Grill and the Greenville Bar and Grill along the 2800 block of Greenville Avenue near Goodwin Avenue, early Tuesday morning.
Dallas Fire-Rescue spokesman Jason Evans said investigators concluded the fire began in the space between the first and second floors near the rear atrium of Terilli's. Investigators said an unspecified electrical short in the fixed wiring was to blame.
Fire investigators earlier said the blaze quickly spread through the attic and collapsed the building's roof.
It was not clear how much, if any of the building, which was built in the 1930s, could be salvaged. All four businesses said they want to rebuild, but it could take at least eight months to restore the historic building.
A Facebook page, Help Lower Greenville, has been set up to assist employees affected by the fire.
NBC DFW's Frank Heinz and Randy McIlwain contributed to this report.