Nehawu members began striking on Tuesday and Numsa members joined on Thursday.
Tumisho Madihlaba, acting branch secretary for Wits Nehawu, said the university’s counter-offer of a 6.8% increase was unsatisfactory.
"We've moved to 12% and they still say they cannot afford this and have offered us 6.8%," he said.
"There is some level of arrogance and the university is undermining us."
The strikers also demanded that the university's lowest income earners be moved to the midpoint of the salary scale.
"Management responded that that is not affordable because it's going to cost them an additional R20m," said Madihlaba.
"The irony, of course, is that this university can afford, at any one given point in time, R41m per annum on [security], who come just to watch property and intimidate students and staff."
Watch here:Zama Buhle, Wits University spokesperson, said the university was making an offer well above the current inflation rate of 4.6%.
"Employees in Grades 16 and 17 [have been offered an 8% increase and] senior management is to receive 6% only," she said.
"This is the best offer that the university can make in order to ensure its financial sustainability."
Buhle added that Wits University's salary increase offer was the second highest offer in the university sector.
The university was granted an interdict following three incidents that took place during the Nehawu strike on Wednesday.
"A senior academic was manhandled and the university approached the Labour Court in order to ensure that staff, students and visitors are not intimidated or harmed [among other demands]," said Buhle.
She said the university recognised the right of workers to strike within the limits of the court order and the university’s policies and processes.
"Anyone who infringes [these limits] will be held accountable in line with the law and the university's rules," she said.
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