The tear gas was fired when the protesters tired to reach Galle Face when the Galle Road from Kollupitiya Junction was closed.
The protest was organized by the Inter University Students Federation (IUSF) against the Batticaloa private university.
The protest march which commenced near the University of Sri Jayewardenepura, passed through Nugegoda, Kirulapone, Thummulla and reached Kollupitiya.
As a result, there was heavy traffic at the Kollupitiya junction this afternoon.