While Libya’s first free national election in 60 years is a cause for celebration by many voters, polling in three eastern cities was suspended due to violence.
Security sources say a group of radical Islamists stormed several polling stations in Benghazi, Ajdabiya and Brega and burned or stole ballot boxes.
Authorities decided to proceed with Sunday’s vote despite a surge in violence and vandalism in recent days.
The election comes after the death of Muammar Gaddafi following 42 years in power.
The polls will choose a 200 member legislative assembly which will elect a prime minister and cabinet and draft the country’s new constitution.
The election has heightened tensions between eastern and western regions. Groups based around Benghazi in eastern Libya complain they will be under represented in the assembly.
Hundreds of people protested through the city on Friday threatening to boycott the election.