Confrontations between protesters and police forces picked up on Wednesday morning in Cairo's Tahrir Square.
Police forces used teargas to disperse the protesters who hurled stones and Molotov cocktails at them.
Al-Jazeera aired footage of tens of protesters gathered near Tahrir Square and by the U.S. embassy amid heavy smoke due to the excessive use of teargas.
The satellite channel also aired footage of ongoing confrontations near Omar Makram Mosque.
Scuffles erupted last week following a demonstration to commemorate deadly clashes that occurred last year resulting in the death of over 40 people.
Tensions escalated on Thursday when President Mohamed Mursi issued a constitutional decree expanding his powers.
Liberal, leftist and socialist forces organized nationwide demonstrations on Tuesday to express their outrage against the decree that they considered a step towards a new autocratic era.