The store and the warehouse were gutted by the fire

They died after the store's roof collapsed on them. The mayor said it was "a tragedy of immense proportions".

The fire began on Monday night, and was described by some witnesses as a "tornado of flames".

Two employees were rescued from the buildings. The cause of the fire is being investigated.

The fire began at about 1900 local time on Monday (2300 GMT) in the Sofa Super Store and warehouse, Charleston Mayor Joseph Riley told reporters.

He said the blaze apparently started in a storage area.

Local residents said the store's roof collapsed, burying the firefighters and throwing burning debris around the building.

"It was like a 30-foot tornado of flames," Mark Hilton was quoted as saying by the Associated Press news agency.

The mayor said the firefighters "extinguished the fire and they lost their lives fighting for the safety of our citizens".

"To lose nine is just a tragedy of immense proportions," he said.