Two Egyptian police conscripts were injured in attacks on police vehicles by Islamist protesters in Alexandria on Friday, Al-Ahram Arabic news website reported.
Loyalists of the banned Muslim Brotherhood staged a march in Al-Mamoura area where they reportedly threw Molotov cocktails at police vehicles as forces attempted to disperse the march, leaving two conscripts injured.
Elsewhere in the Mediterranean city, police arrested seven Islamist protesters in similar marches.
Alexandria has seen almost weekly demonstrations since the ouster of Islamist president Mohamed Morsi last year.
Police also dispersed similar small protests in Beni Suef, Fayoum and Giza on Friday.
Egyptian authorities banned unauthorised protests in November last year putting restrictions on public assemblies deemed repressive by rights activists.
The Muslim Brotherhood, banned by the government and declared a terrorist organisation, has staged along with allies regular protests since Morsi's ouster against the current government.
It has also demonstrated against the detention of its members, especially on university campuses.
The group, however, has reiterated its commitment to peaceful demonstrations. Yet a large number of people have been killed in recurrent clashes since the ouster of Morsi.
The government has arrested hundreds of people over the past year under the provisions of the protest law. It has also launched a crackdown on the Brotherhood putting dozens of its top leaders, including Morsi, on trial.