Police appeared to set off two percussive grenades, causing loud bangs, to drive the workers out of a parking lot under the Moses Mabhida Stadium in Durban hours after Germany beat Australia 4-0 in Group D.
Associated Press reporters saw about 30 riot police charge into the crowd to drive it out of the stadium. While calm quickly returned to the stadium, some of the security stewards, wearing orange and green jackets, continued milling around outside.
An AP photographer said police fired tear gas at protesters outside the stadium. A nearby street was littered with trash where the protesters were forced away. Concrete blocks had been pushed into a street.
About 100 police later surrounded a group of about 300 protesters on a street near the stadium and separated the men from the women. An AP photographer said he heard police tell the protesters they would be arrested for causing a public disturbance.
The protesters later left peacefully after calm discussions with police. There were no injuries or arrests reported.
Repeated calls to police in Durban seeking comment were not returned.
A FIFA spokesman declined to comment immediately and the local organizing committee for the World Cup did not immediately respond to telephone calls and e-mails seeking comment. The police command set up in Johannesburg for World Cup-related matters was aware of the protest but had not received an official report from Durban.
Police were called to the scene after hundreds of angry stewards gathered to complain about their wages.
"We left our homes at seven in the morning and now it is nearly 1 o'clock," said Vincent Mkize. "In the dry run, they didn't want to tell us how much we would get."
Another of the stewards, Fanak Falakhebuengu, told the AP he had heard they would be paid 1,500 rand ($195) a day but were only getting 190 rand ($25).
"They were supposed to give us 1,500, that's what FIFA told us and they gave us 190. We are working from 12 o'clock until now," said another man who asked not to be named. He ran from police before he could give his name.
Many of the protesters were waving small brown envelopes that had held their pay. One handed to a reporter had the figure 190 written on it under "amount payable."
Others said they had been abandoned at the stadium after the match and would have to walk about four hours to get home. They said no transport was provided for them.