Egypt (and Beyond) Live Coverage: Mubarak's Police Behind Almost 900 Killings of Protesters in 2011 Uprising
Opposition society Al Wefaq said that at least 35 protesters had been hurt, three of them critically.
The Ministry of Interior claimed "domestic terrorists" had blocked roads and burnt cars. It said two police officers were injured.
Witnesses reported heavy clashes as police used tear gas and stun grenades against youths who, according to the Ministry of Interior, carried "Molotov cocktails, iron rods, and a number of homemade bombs."
In March 2011, the other members of the Gulf Co-operation Council sent in troops to back up Bahrain's security forces, who overran the camps of protesters, including the main one at the iconic Pearl Roundabout.