Clashes erupted in central Cairo on Saturday as police used tear gas and rubber bullets to disperse protesters and prevent them from staging a sit-in in Tahrir square, activists said, dpa reported.
Protesters threw rocks at security forces while chanting slogans against the Interior Ministry and the country's military rulers.
The Ministry of Health said five people were injured.
Tahrir Square was the centre of anti-government protests which led to the ouster of president Hosny Mubarak earlier this year.