Police fired tear gas at anti-government protesters in downtown Belgrade as they clashed for the third day on Friday in the Serbian capital and other cities amid reports of police brutality and excessive use of force during the unrest.

The anti-government rallies were held on Friday night across Serbia under the slogan: “Let’s show them we are not a punching bag.”

Police deployed armored vehicles in parts of the capital as protesters faced off against riot police separating them from pro-government supporters in downtown Belgrade.

Groups of protesters, most of them wearing facemasks, fired flares and threw rocks and eggs at the riot police, who charged them while mounted on armored vehicles in the wide boulevard in front of the Serbian government headquarters.

Some people were seen getting first aid, but there were no immediate reports of how many were injured.

Thrash cannisters were rolled onto the streets, some set on fire. The chaotic scenes in Belgrade were repeated in similar clashes in several other cities and towns.

Earlier Friday, Serbian police said they detained hundreds of demonstrators who took part in anti-government protests throughout the country this week.

The three days of clashes between the police and loyalists of autocratic President Aleksandar Vucic on one side and the anti-government protesters on the other have left dozens injured or detained.

The unrest marked a serious escalation of more than nine months of largely peaceful demonstrations led by Serbia’s university students that have shaken Vucic’s firm grip on power in the Balkan country.

The protests that rattled Vucic first started in November, after the collapse of a renovated train station canopy in Serbia’s north killed 16 people.

Many blame the tragedy on alleged corruption-fueled negligence in state infrastructure projects.

Several social media posts from this week show baton-wielding riot police beating people to the ground and then kicking them with their boots before they were handcuffed. The apparent targets were often women and young people.

Serbia’s Interior Minister Ivica Dacic denied Friday that police used excessive force, blaming the demonstrators for allegedly attacking the officers, who were protecting themselves with riot shields.

AP Video shot by Marko Drobnjakovic