An AFP correspondent in Egypt reports that gunfire erupted outside the Cairo headquarters of the Republican Guard.
Supporters of ousted Egyptian president Mohamed Morsi gathered there, vowing to defend him.
The report notes that shooting could be heard coming from both the Republican Guard and the protesters, and that wounded protesters fell to the ground.
The Republican Guard, the senior-most Corps in the Egyptian Army and one of its largest Divisional commands, is an armored division with the main responsibility to defending the Capital of the Republic (mainly the major government and strategic industrial institutions).
Earlier Reuters reported that on Thursday about 80 people were injured in Zagazig, a Nile delta city where Morsi has a family home.
Business Insider has a correspondent on the ground.
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