At least 34 people were injured in clashes between Muslim Brotherhood protesters and opposition Rebel campaigners in Fayoum on Sunday night, Al-Ahram Arabic news website reported.
Around three thousand Islamists were marching in support of the new governor of Fayoum, a member of the Muslim Brotherhood appointed by President Mohamed Morsi.
Clashes started when some Islamist demonstrators confronted Rebel campaigners collecting signatures for an anti-Morsi petition in Fayoum's Revolution Square.
Rebel spokesperson Mohamed Hamdi said Brotherhood supporters carrying bats and helmets approached Rebel campaigners.
“They broke tables and chairs, and destroyed tens of petitions.”
Rebel activist Ayman Bakry was injured and had his camera stolen, Hamdi added.
The Islamist marchers continued to the working class Hawatem district where there were confronted by angry locals who attempted to drive them from the area.
Rebel aims to collect 15 million signatures in support of a vote of no confidence in President Morsi, to outnumber the 13.2 votes he won in last year's presidential election. It had collected more than seven million signatures by late May.
Members of Rebel have been subject to intimidation, physical assaults, brief arrests and abductions since the group's inception.
Supporters of President Morsi say the Rebel campaign is anti-democratic because it wants President Morsi to call early presidential elections.