Clashes erupted after Friday prayers across Egypt as thousands of supporters of ousted president Mohamed Morsi attempted to demonstrate against the military government that deposed him.
Health Ministry officials said four people were killed in the clashes in Cairo between the Islamist supporters of Mr. Morsi and Egyptian security forces. The fighting broke out when Morsi supporters tried to converge on Tahrir Square, a focal point in the last three years of dissent and demands for political and social change.
Another 40 people were wounded nationwide.
More demonstrations are expected Sunday when Egypt marks the anniversary of its 1973 war with Israel.
Egypt's interim military government says the crackdown against protests is a defense against terrorism.