Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
The ANC yesterday called on all South Africans to acknowledge the contribution made by workers to the struggle for freedom.
On the day historically known elsewhere as May Day, but called Workers' Day in South Africa, the party said it saluted the workers of South Africa. It sent a message of solidarity to the workers of Africa and the world.
"This day is celebrated in a democratic South Africa thanks to the tireless struggles and sacrifices that workers have made over many decades," the ruling party said in its Workers' Day message.
The party said the day was "a fitting reminder of the efforts of the workers to forge a new society, free from discrimination, oppression and exploitation".
The ANC said that during the struggle against apartheid, the fight for recognition of Workers' Day as a paid public holiday, and for legal protection of the rights of workers, had provided impetus to the struggle.
The commemoration of Workers' Day, the party said, was a reminder of the road South Africa still had to travel to eradicate the legacies of apartheid and colonialism, and to achieve a better life for all.