Officials are working to restore electricity after two large power plants in 10th Ramadan City that supply vast swathes of the capital broke down Wednesday, an informed electricity company source said.
The source told Al-Masry Al-Youm that the sudden failure forced officials to deactivate the plants to prevent damage to the national electricity network and electronic devices in people's homes.
The districts of Shubra, Giza, Nasr City, Heliopolis and central Cairo were affected by the blackout.
The problem at the plants lasted 30 minutes, but the source said it takes time to get them up and running after a shutdown.
The power outages paralyzed most institutions and government departments downtown, as well as the metro system.
Stock exchange management opened trading an hour late, at 11:30 am, due to the outages and ordered trading extended an hour until 2:30 pm to compensate.
The country has been suffering frequent power cuts over the last few weeks, prompting protests in many governorates. Some activists have called on people to refrain from paying their electricity bills.
Edited translation from Al-Masry Al-Youm