Dawn newspaper said firemen early Friday were still battling the blaze, which erupted Thursday in the Lahore Development Authority Plaza on Edgerton Road in the central part of the city, which is the capital of the Punjab province and Pakistan's second largest after Karachi.
It was not immediately known how many people were in the building when the fire started. The Express Tribune said at least 15 people were believed missing.
Some of those in the building managed to reach the roof from where they were rescued by military helicopters.
Among the dead, four died after jumping from window sills, the report said.
The fire, which started on one of the upper floors, quickly spread to the other floors, fire officials said.
The Tribune said authorities suspect an electric short circuit on the seventh floor might have started the blaze.