Egypt unrest: Rival groups battle over Tahrir Square
On the 10th day of turmoil in Egypt anti-government protesters fought back against supporters of President Hosni Mubarak, pushing them out of some streets in central Cairo which they controlled.
Stones were thrown on both sides, and the army appears to have failed to control the crowds.
President Mubarak has claimed he is tired of being in power but that leaving office now would simply lead to more chaos.
Jeremy Bowen reports.