The incident reportedly left eight individuals injured.
Since it started monitoring the situation on January 13, the agency has been alarmed to see individuals at protest sites with weapons, including firearms. At the same time, explosives and guns have been used against the protest groups by unknown perpetrators, it said.
“OHCHR is highly concerned that this situation could lead to further outbreaks of serious violence and armed confrontations,” the UN said in a statement.
OHCHR calls on all sides to refrain from carrying weapons or resorting to violence, it said, and urged the authorities to investigate and hold to account those responsible for the violence.