Two days of protest across Egypt have left at least four people dead.
In the photograph above, Egyptian riot police gather near burning tyres as a demonstrator throws an object at them.
The government says the protests are illegal and has launched a crackdown, reportedly arresting up to 1,000 people.
Hosni Mubarak has ruled since 1981 and dissent is rarely tolerated. This uprising was inspired by unrest in Tunisia earlier this month, in which President Zine al-Abidine Ben Ali was ousted.
Above, police fire tear gas to disperse crowds. Many were beaten with batons.
Protesters in Cairo pray. Organisers have stressed that the religion of protesters is not relevant, and urged them to come out in force again after attending prayers in mosques and churches on Friday.
Mohamed ElBaradei, Nobel laureate and opposition figure, says he is returning to Egypt today (Thursday) to take part in the protests.
All photographs: AFP/Getty Images.