Police have arrested about 100 people in St. Paul during protests of the recent police killings of black men, including one outside Minnesota’s capital city.

Authorities say 21 St. Paul officers and six state troopers were hurt during the fracas late Saturday and early Sunday.

St. Paul Mayor Chris Coleman and Police Chief Todd Axtell are condemning the violence. Axtell calls the pelting of officers with rocks, bottles and other objects “a disgrace.”

The Star Tribune reports about half the arrests came during a blockade of Interstate 94 in St. Paul. About 50 arrests were made early Sunday in another part of St. Paul. The interstate reopened early Sunday morning.

The protest was among several demonstrations nationwide following the deaths of 32-year-old Philando Castile in suburban St. Paul and 37-year-old Alton Sterling in Baton Rouge, Louisiana.