Three people have been killed and 265 arrested in a crackdown on demonstrations in favour of Egypt's Muslim Brotherhood, which has been declared a terrorist group.
The three people were killed on Friday as Islamist protesters clashed with police and opponents in several cities, the interior ministry said.
Spokesman Hany Abdel Latif accused the protesters of using firearms and petrol bombs, telling AFP they "increased their violence" in Friday's rallies.
The interior ministry said police arrested 265 "Brotherhood elements" in the clashes.
Egypt's military-installed government has banned protests by Brotherhood members, who have been demanding the reinstatement of deposed president Mohamed Morsi.
"Legal measures are under way against the Brotherhood elements in accordance with the cabinet's listing of the Muslim Brotherhood as a terrorist organisation," the ministry said in a statement.
Leaders could be sentenced to death and supporters face up to five years in jail.
The decision to blacklist the Brotherhood came a day after a suicide bombing of a police building killed 15 people.
The government blamed the attack on the Brotherhood despite a claim of responsibility from a Sinai-based jihadist group.
Tensions rose even further after a home-made bomb exploded next to a bus on Thursday, wounding five people.
The Brotherhood, which condemned Tuesday's suicide bombing, has denounced its listing as a terrorist organisation and vowed to continue staging peaceful rallies.
It has held near-daily protests since the military ousted Morsi on July 3, despite a crackdown that has killed more than 1000 people, mainly Islamists, and led to thousands of arrests.
