The confrontations came as the Chamber of Deputies was set to hold a final vote Wednesday night on the entire austerity package. Premier Silvio Berlusconi hopes to fend off a financial crisis that could threaten the entire 17-nation eurozone.
An AP reporter saw hundreds of people, some hurling smoke bombs, march through streets near Parliament. Storekeepers near the Pantheon monument in the neighbourhood hastily shuttered display windows.
As police helicopters buzzed overhead, riot police fanned out through the squares and alleys, herding the protesters away from Parliament and from the downtown palace where Berlusconi resides. At one point an officer struck a protester on his back with a club.