According to an FIR registered in the Town police station, some Afghan refugees blocked the main university road at Bab-e-Peshawar in Hayatabad while protesting against Talibanisation in Afghanistan.
They raised anti-Pakistan slogans and ransacked public property.
The police rushed to the protest site to disperse the mob but the protesters started pelting stones at them and in the process, some policemen suffered injuries.
The police said eight protesters were arrested.
Twenty-three more Afghans, who were holding another protest on the university road, were arrested on the same charges.
Those arrested have been accused of fanning hatred on the basis of race, ethnicity and culture in the province, according to the FIR.
They have been booked under sections 148, 149, 153 of the PPC and 14FA, the police added.