University of Johannesburg lecture hall in Bunting Road campus has been set alight.
EWN reporter Dineo Bendile says students were attending lectures while others gathered in a meeting to discuss Thursday's events when the fire broke out.
The university said it does not want to speculate until investigations are completed.
This was totally unexpected. There wasn't even the police here. Things were continuing as normal. Students were attending lectures.— Dineo Bendile, EWN reporter
Meanwhile, President Jacob Zuma has released a statement calling for calm and peaceful protests across universities.
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