Black-clad activists stormed Portland City Hall on Wednesday to protest the city’s crowd control techniques used by police during last Saturday’s counter-protest of a conservative march. The group assaulted one security guard with a megaphone and scuffled with several others, reports Oregon Live.

Some of those who say they were injured by officers dressed in military gear and wielding batons or non-lethal munitions were on scene Wednesday, trying to speak with city officials.

One demonstrator, who was masked and wearing a baseball helmet, smashed a security guard over the head repeatedly with a megaphone. The guard was seen afterward clutching a bag of ice, a bruise beginning to form on his cheek. –Oregon Live

City Hall chief of security, Dorothy Elmore, reports being struck in the arm by a protester, while an unidentified bandana-clad man who was found sprawled on the floor outside the mayor’s office was arrested and carried out by his arms and legs. Also arrested was 67-year-old Diane Keeauve, according to Portland police spokesman Sgt. Chris Burley.