More video of Tahrir Square chaos as stones fly, gunshots heard in Cairo - Thousands of supporters and opponents of President Hosni Mubarak battled in Cairo's main square on Wednesday, raining stones, bottles and firebombs on each other in scenes of uncontrolled violence as soldiers stood by without intervening. The two sides crouched behind abandoned trucks and hurled chunks of concrete and bottles at each other. A tank was later set on fire at Tahrir Square, as anti-Mubarak protesters attempted to shelter behind it.