A volunteer doctor treating the wounded said at least 15 people had been killed, Bikyamasr.com reported. Khaled Ali, a leftist lawyer and presidential candidate, told Egypt Independent he had counted at least 20 bodies, while the official death toll was nine.
Protesters said the men who attacked them with rocks and Molotov cocktails were carrying meals supplied by the military. The army also deployed tanks around Abbasiya Square, site of the Defense Ministry.
The protests began late last week as a demonstration by supporters of Hazem Saleh Abu Ismail, a Salafist candidate who was disqualified from running for president. But activists say it grew into a protest against military rule that united the Salafists and Muslim Brotherhood with those on the left end of the political spectrum.
Activists said one big issue is a constitutional provision that disqualified candidates cannot appeal the Presidential Elections Commission decision.
"I just want to make it known this is not an Abu Ismail supporters' protest, this is against military rule and the unjust circumstances surrounding the presidential campaign," Ali said.
Hundreds of people remained in Abbasiya Square late Wednesday. But Ahram Online said the violence appeared to have stopped.
At least two presidential candidates suspended their campaigns because of the violence.