"The so-called 'blackface' incident where two white students... depict themselves as black domestics is not only distasteful but also racist to the extreme," Sasco president Ntuthuko Makhombothi said in a statement.
"Black women in our country continue to suffer from triple oppression as black, female, and working class. This incident ridicules the situation of black women in our country and reinforces racist stereotypes about our mothers."
Probe launched
The picture shows two female students in domestic worker outfits with black paint smeared on their faces and arms. They pose with headscarves and padded bottoms. The picture has gone viral on social networking sites on Wednesday.
The University of Pretoria (UP) earlier told Sapa it had launched an investigation into the possibly racist behaviour.
"The investigation began yesterday," UP spokesperson Nicolize Mulder said.
"The university... will not tolerate any form of discrimination and/or racist behaviour by any of its staff or students. The behaviour by the students in the photographs is completely unacceptable."
Mulder said the picture was taken at a private 21st birthday party but because they were students at the institution, action would be taken.
"Because the students are registered UP students who by their actions brought the name of the university into disrepute, disciplinary steps against the students have been taken," she said.
White youth taught to disrespect black suffering’
Sasco said it felt "particularly angered".
"It is clear to us that the white community assisted by institutions of white privilege, like UP, are teaching white youth to disrespect and poke fun at black suffering," he said.
"Clearly the myth about reconciliation in our country, propagated by white reactionary media, is an illusion."
The continued existence of "institutions of white privilege" was an untenable "crisis".
"Black students will not fold their arms as their suffering and that of their parents is made fun of. The dignity of Africans cannot be trampled on without consequences to the perpetrators.
"We have absolutely no confidence in the supposed disciplinary action the university seeks to institute against their precious white students."
The SA Human Rights Commission said it was not investigating the case as it did not receive a complaint.