For the last 14 days, the world has watched as hundreds of thousands of Egyptians have thronged the streets to protest - and then battle it out - in a popular uprising against the 30-year-old regime of President Mubarak. Panorama's Jane Corbin has been filming inside these extraordinary scenes - in the main squares with the protest organisers, and in the mean back streets where vigilantes and undercover police fight for control in a tense and terrifying struggle for power.