Muslim Brotherhood supporters and police clashed across Egypt on Friday, leaving at least three dead in protests after the army-backed government declared the group a terrorist organization.
Violence broke out after Friday prayers.
An 18-year-old Brotherhood supporter was shot dead during clashes in the Nile Delta city of Damietta. Another man was killed in Minya, a bastion of Islamist support south of Cairo. A third person was killed in Cairo, the interior ministry said, without giving details.
Meanwhile, security forces detained at least 265 Brotherhood supporters.
The widening crackdown has increased tensions in a country suffering the worst internal strife of its modern history since the army deposed Islamist President Mohamed Mursi in July.
Security forces have killed hundreds of his supporters, and lethal attacks on soldiers and police have become commonplace.
The Brotherhood was declared a terrorist organization after 16 people were killed in a suicide attack on a police station on Tuesday, although the group condemned the attack and it was claimed by a radical faction based in the Sinai Peninsula.
The Muslim Brotherhood and its Islamist allies had called for protests in response to the government decision.
Clashes between police and protesters flared in Cairo and at least four other cities on Friday.
Police fired birdshot and tear gas at student protesters at Al-Azhar’s Cairo campus. Gunfire was heard in the Suez Canal city of Ismailia, where demonstrators threw fireworks and rocks at police who used teargas, a Reuters witness said.
A number of police officers were injured in the clashes, the interior ministry said.
