JOIN USThe official MENA news agency reported that police moved into Tahrir Square in the morning to break up the sit-in, which also included relatives of victims killed during the revolt that overthrew president Hosni Mubarak in February.
An AFP correspondent reported clashes later between riot police and roughly 200 protesters, who flung whatever they could at policemen who beat them with sticks.
A security official said police arrested several protesters.
The sit-in, which had gone for some days, called for speedy trials of policemen and officials accused of involvement in the deadly crackdowns during the 18-day revolt that ousted Mubarak.
Mubarak is on trial along with his former interior minister and security chiefs on charges of ordering the killings of some of the roughly 850 people killed during the uprising.
The sit-in was joined on Friday by some tens of thousands of protesters who flooded the square to demand a quick transition to civilian rule.
Friday's demonstration, which was spearheaded by Islamist groups, also called on the military appointed cabinet to withdraw a constitutional draft that would prevent parliamentary scrutiny of the military's budget.
The military, in charge since Mubarak's resignation on February 11, says it will handover power after a yet unscheduled presidential election.
Parliamentary elections will start on November 28.