Tens of thousands of protesters are expected to demonstrate Saturday at the World Summit on Sustainable Development. Several protest marches are scheduled to converge on the conference center.
Saturday is protest day. Four separate marches are on the schedule, although they may merge as the day goes on.
Organizers of the two larger events say they expect between 10,000 and 15,000 people for each march. They are coming to protest a host of issues, including globalization, the privatization of South African state industries, and the summit itself.
Thousands of South African police officers have been brought in from all over the country. They are backed up by members of the armed forces and U.N. security staff.
Officials from the South African government and the city of Johannesburg have vowed to crack down on illegal, unregistered protests. They want to ward off the violence that has accompanied several other large international meetings in recent years.
But they have agreed to allow the anti-summit protesters to march on the convention center. Officials were accused of suppressing freedom of speech last week. Police arrested 77 people last Saturday at an unregistered march near the campus of the University of the Witwatersrand.
South African officials say they respect peoples' right to protest, but they will not tolerate what they call anarchy at the demonstrations.
One of the larger marches scheduled for Saturday is organized by a coalition of activist groups calling themselves the Social Movement Indaba. A spokesman for the group told reporters they intend to march peacefully. He says, if there is any violence, it would be coming from the police.
Several small protests have been held throughout the week, none attracting more than a few hundred people.
At one protest Friday, police outnumbered demonstrators 8:1. 15 people held banners aloft as 120 officers in riot gear looked on.