Residents from at least two residential buildings had to flee their homes after fires threatened the structures on Thursday.
Two levels of an eleven storey building in Hillbrow were destroyed in the blaze.
While a ten storey apartment block also caught alight in downtown Johannesburg.
The 24-year-old said more than a 100 people were staying in the building.
“When the fire started, two people jumped from the fourth floor. Everyone was shocked and they had to run away, bra. You know what I mean,” she said.
Johannesburg Emergency Management Services spokesperson Nana Radebe said seven people had been confirmed dead.
“One jumped and six other died of smoke inhalation,” Radebe said.
Radebe said seven others had been taken to hospital. Two of the seven had burn wounds to their hands and feet.
Over 50 people had been rescued from the building.
Radebe said the fire had been extinguished