After President Mubarak declared he would not run for-re-election last night, President Obama went on TV with his assessment of the ongoing protests in Egypt. At today's White House briefing, press secretary Robert Gibbs would not elaborate on whether the President was calling on Mubarak to step down immediately, rather than serving out his term, which ends in September. Meanwhile, after nine days of peaceful protest, Tahrir Square erupted in violence today as Mubarak loyalists arrived on the scene. Men on horses and camels beat anti-government protesters. Thugs attacked reporters and TV crews. As darkness descended, Molotov cocktails started fires in crowds of men, women and children, and there was the sound of gunfire. But, despite the presence of tanks and armored personnel carriers, there was no indication that the military was trying to restore order. It's now evening in Cairo. We hear from reporters and others about the developing scene, see how the Obama Administration is reacting, and talk to observers about repercussions in other Middle Eastern countries.