Egyptian security forces and protesters are clashing for a second successive day in central Cairo in scenes not seen since the uprising that toppled Hosni Mubarak early this year, AP reported.

Riot police have deployed around the Interior Ministry and are using tear gas to keep protesters at bay. The demonstrators were responding with rocks and firebombs.

So far, Wednesday's violence is on a much smaller scale than the clashes the previous evening, when some 5,000 protesters battled the police for hours overnight.

Many of the protesters are believed to be relatives of some 850 people killed during the uprising that ousted the former president, and are frustrated over what they perceive as slow pace of prosecution of officers believed to be responsible for the deaths.