Four people were arrested on the N8 near Botshabelo on Thursday for trying to block the road, police said.
Col Vish Naidoo said traffic officials at Botshabelo, some 60 kilometres west of Bloemfontein, warned police of an possible attempt to block the road.
“The group attempted to block the road, but police arrived in time to disperse the crowd.”
It was alleged that the group were unhappy ANC centenary marshals left out of the event accreditation process.
Naidoo could not confirm the reason for the protest action, but indicated the behaviour of the individuals was something police could not allow.
“The behaviour was unacceptable,” said Naidoo.
The group managed to throw some stones on the road and a tyre was burned on the road.
Police would remain in the area to monitor the situation, Naidoo said. - Sapa