The fire reignited three days after a major fire at the country's telecommunications hub resulted in four fatalities and widespread service disruptions.
Civil defence teams responded to the scene and contained the recent blaze, authorities said.
Photos and videos indicate that Wednesday's fire occurred in a different location from the first incident
On Monday afternoon, a fire erupted on the seventh floor of the Ramses Central telecommunications exchange building.
The incident led to widespread disruption of internet and phone services for at least three days.
At least 27 others were injured in addition to the four fatalities.
Preliminary investigations suggest the initial fire was caused by an electrical short circuit, although a full technical report is pending.
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