At least 49 people have been killed in clashes in Egypt as the country marks the anniversary of the 2011 uprising which overthrew President Hosni Mubarak, the health ministry says.
Rival demonstrations of supporters and opponents of the military-backed government took place in Cairo.
But police broke up anti-government protests, and arrests were reported in Cairo and Alexandria.
Hundreds have died since July when the army deposed President Mohammed Morsi.
Egyptian Interior Minister Muhammad Ibrahim had urged Egyptians not to be afraid to go to events marking the anniversary of the uprising.
Thousands of supporters of the military and the government gathered in high-profile locations including Tahrir Square – the focal point of the 18-day 2011 popular revolt.
Participants waved Egyptian flags and banners showing army chief Gen Abdel Fattah al-Sisi, whom many urged to run for president.
Meanwhile on Saturday, an army helicopter crashed in the restive Sinai peninsula, with an unconfirmed report that its crew of five soldiers was dead.
A large car bomb exploded near a police building in Suez, at the southern entrance of the Suez canal, with reports that nine people were injured.
At least 18 people died in violence on Frid