ANKARA, Turkey — Nov 29, 2014, 9:38 AM ET

Riot police have dispersed a protest by dozens of students near Turkish President Recep Tayyip Erdogan’s new, contested 1,000-room palace.

Police on Saturday used shields and pepper spray to prevent the students from marching to the palace that has become an emblem of Erdogan’s increasingly authoritarian style of governing. Video footage showed one officer punching a student in the face as he was being held by another officer. Twenty-two students were arrested, reports said.

The $630 million palace has drawn the ire of opposition parties, environmentalists and human rights activists who say the construction is too extravagant, destroyed thousands of trees and went ahead despite a court ruling.

Pope Francis, who is on a three-day visit to Turkey, became the first foreign dignitary to be welcomed at the complex Friday.