BLOEMFONTEIN, South Africa — Two white students behind a video in which five black university workers appear to be duped into eating food tainted with urine apologized and said they had been "crucified as racists."

Meanwhile, a magazine said Friday that one of its black journalists covering the video story had been assaulted in what appeared to be a racial attack at a restaurant in Bloemfontein.

Themba Makamo, 26, had to receive stitches after been accosted at his table by a "burly white man" who later followed him to the bathroom, where he headbutted, kicked and punched the journalist in the face and used racially derogatory words, the news and entertainment magazine Drum said in a statement.

Bloemfontein police spokeswoman Superintendent Annelie Wrensch said the complaint was being investigated.

The video, which showed four middle-aged women and one man on their knees eating the food, has been seen around the world, exposing deep racial tensions in South Africa more than a decade after racist white rule ended.

The University of the Free State in the city of Bloemfontein, 400 miles south of Johannesburg, is regarded as a bastion for Afrikaners, descendants of Dutch settlers who are often most closely linked with apartheid rule.

The two students, Roelof Malherbe and Schalk van der Merwe, who have been banned from the university's campus, said in a statement issued by their lawyer late Thursday that although it appeared as if the food had been urinated on, a "harmless" liquid had been squirted from a bottle.

The two students, said they regretted making the film, which they said they meant as a "satirical slant" on the issue of racial integration at the university dormitories.

Malherbe and Van der Merwe are "not racists and, most certainly, had no intention of humiliating or degrading the employees concerned or black people in general or of detrimentally affecting their dignity," the statement said.

However, it said the students "now regret having participated in the making of the film" and "apologize for any embarrassment which they may, unintentionally, have caused to any person or group of persons, including their parents."

Authorities at the university have launched a criminal probe into the making of the video.

On Thursday, the four female university workers expressed their hurt at the video and said they had not been aware of what they were participating in, believing they were taking part in a competition.

"We feel pain," said Emma Koko, 40, who has been working for the university for 20 years and whose son attends classes there. "It's something we were not expecting. We regard them (the students) as our children."

The video depicts a mock initiation ceremony into a campus residence, with the middle-aged black cleaners portraying students. The workers seem to know and trust the students in the video, laughing as they try to eat the food while on their knees. But according to the video footage, one of the students urinated on the food beforehand, unknown to the cleaners.

Commentary on the video in Afrikaans included sarcastic reference to the university's policy of integrating the campus dorms — being phased in only this year, 14 years after the end of apartheid.

In the statement, the two students said that the four women workers were "loyal friends" and took part voluntarily in the making of the film and "as is evident clearly enjoyed it."

The students said the workers knew the film was being made, what its purpose was and that the "brew was not contaminated."

The statement went on to say that it was "suspected that the film was published with malicious intent at a time when it would — and apparently did — purport to serve the purpose of demonstrating racism on the campus."

The university, known for its science departments, is one of a handful of institutions set up for the Afrikaans elite across the country. They all have high academic standards but are seen as conservative and have struggled with racial integration since opening their doors to black students in the early 1990s.

Black students make up 60 percent of the Free State university's 25,000-strong student body. Most of the support staff are black but over 80 percent of teaching staff are still white.

Students say racial tensions on the campus remain high and that the residence where the video was made has a particularly bad reputation.