A structure 20 feet wide and 30 feet tall collapsed, trapping the 63-year-old man and his 36-year-old son in the basement of the building, fire officials said.
They were taken to the hospital in serious condition, and are expected to survive.
A business owner who works near the collapse site said the father was "pretty shaken up."
Fire officials said a natural gas explosion caused the collapse. Authorities are checking for gas leaks in nearby stores.
Officials combed the wreckage and used dogs to try to determine if anyone else may be trapped inside the building, but fire authorities say they're confident the father and his son were the only ones hurt.