Durban - The University of KwaZulu-Natal (UKZN) confiscated 12 petrol bombs and two 5l containers of petrol at its Malherbe residence in Pietermaritzburg, it said on Thursday.
UKZN said it had been alerted to increased protest activity on some of its campuses.
"Security services are monitoring the situation and will take action against anyone found to be violating the High Court interdict currently in place."
At its Pietermaritzburg campus, a test was disrupted by protesters on Wednesday.
"There have been reports of attempts to block roads, acts of arson, and the letting off of fireworks in enclosed spaces. Risk Management Services confiscated 12 petrol bombs and two 5l containers with petrol inside the Malherbe residence," it said.
The university asked students and staff to remain vigilant regarding their personal safety and security.
"Anyone who notices anything that may raise security concerns, is urged to report this to RMS on their respective campus."
A student was arrested at Howard College campus after a group of students disrupted lectures.
The institution said its security service was monitoring a group of students who were moving between the residences gathering stones.
It warned that action would be taken against individuals spreading racist and discriminatory messages on social media.