Hundreds of Egyptians have taken to the streets to protest against President Mohamed Morsi and the Muslim Brotherhood, whose political wing controls the post-revolution's first elected government.
Protesters battled police in several Egyptian cities on Saturday, with at least eight people reported injured, after rallies to mark the anniversary of a key opposition movement turned violent.
In the capital, Cairo, police fired tear gas at hundreds of protesters outside the Superior Court, which also houses the offices of the public prosecutor who had opened investigations against several dissidents.
"We are Muslims but we want a civilian state."
- Saffeya Mustapha, protester in Cairo
The prosecutor-general angered activists a week ago by questioning a popular TV satirist who is accused of having insulted Morsi.
The government denies opposition claims that the case is evidence of a crackdown on dissent.
About 500 people marched for much of the day through central Cairo, chanting "The people want to topple the regime".
"We are Muslims but we want a civilian state," said Saffeya Mustapha, a protester on the Cairo march.
Live television showed footage of protesters throwing stones at police in armoured vehicles, amid burning tyres on a main road near the court.
The police fired heavy volleys of tear gas.
Police also fired tear gas at protesters in the coastal city of Alexandria and in the Nile Delta city of Mahalla, where demonstrators attacked a police station with petrol bombs, the official MENA news agency reported.
Opponents and supporters of the Muslim Brotherhood attacked each other with stones and fireworks in Alexandria, MENA said.
The rallies were organised to mark the fifth anniversary of the April 6 protest movement, which took off after a deadly police crackdown on a labour strike in textile town of Mahalla on April 6, 2008.
The Mahalla clashes marked an escalation in the burgeoning protest movement against long-time ruler Hosni Mubarak, eventually overthrown in a 2011 popular uprising.
Morsi has faced an intractable opposition which spearheaded mass rallies after he assumed broad powers in November that have since been repealed.
Two years after the uprising that overthrow Mubarak, Egypt is still trying to find its footing in a declining economy and often violent protests that have kept away much-needed tourist revenues and foreign investments.
The country is in talks with the International Monetary Fund for a $4.8bn loan aimed at restoring investor confidence.