Egyptian news service al-Ahram reports at least nine people died in clashes in the Abbasiya district of Cairo.
The report states that government forces arrived at building housing the Defense Ministry in response to skirmishes between area residents and supporters of banned presidential candidate Hazem Abu-Ismail, a Salafist.
Volunteer doctors treating those injured during the melee reported that live ammunition and tear gas were used against demonstrators.
The attacks that left nine dead were attributed by al-Ahram to "plainclothes men."
The Egyptian military has since stated the situation is under control.
Former Muslim Brotherhood leader and Islamist candidate Abdeul Moneim Abul Fotouh and Revolutionary Socialist Khaled Ali announced they would suspend their campaigns to protest the violence.
Campaigning started this week for the election in May. Lawmakers had protested allegations that military rulers were considering postponing the vote, however. A source in the ruling Supreme Council of Armed Forces told the news service the allegations were baseless.