Tens of thousands of anti-globalization activists have rallied in Seoul to protest a summit of the Group of 20 major economies later in the week.
South Korean labor rights campaigners and other protesters gathered in a large plaza near Seoul's City Hall Sunday, chanting slogans and singing songs denouncing the G-20.
The activists accuse the world's biggest economies of violating workers' rights and threatening social welfare programs by cutting public spending. South Korean police estimated the size of the rally at 20,000, while organizers said it drew 40,000 people.
Thousands of police surrounded the rally, which was largely peaceful. Some demonstrators tried to march away from the designated protest zone and scuffled with police, who forced them back with pepper spray.
South Korea's government has deployed 50,000 police around Seoul and placed the military on high alert ahead of the two-day summit that begins Thursday. U.S. President Barack Obama is due to be among the world leaders in attendance.
South Korea is concerned that anti-globalization protesters, terrorist groups and North Korea will try to sabotage the event.
The activists who rallied Sunday also oppose a proposed free trade agreement between the United States and South Korea. Mr. Obama has said he wants to finalize that deal before the summit.
Some information for this report was provided by AP, AFP and Reuters.