Johannesburg - US actor and activist Danny Glover surprised Popcru members at Mary Fitzgerald Square in central Johannesburg on Thursday.
He told the crowd he supported them.
"I'm here on behalf of all the workers in Mississippi. We are all supporting each other, we must stand together. Amandla," he said.
He was accompanied by president of the United Automobile Workers' Union of America, Bob King.
The National Union of Metalworkers of SA had invited the two.
Police and Prisons Civil Rights Union (Popcru) members in Gauteng are taking to the streets to demand that the SA Police Service honours an agreement to change administrative staff salary grades.
Sapa