Windsor police arrested a suspect at Sunday's anti-mask protest in downtown Windsor.
The man faces two charges; obstructing a police officer and failing to comply with the Reopening Ontario Act.
While Windsor police took the man into custody at the protest, Sergeant Steve Betteridge could not say if the alleged offences are related to the demonstration.
About 50 people took part in the protest.
Meanwhile, Windsor by-law enforcement officers laid 23 charges during a pro-active blitz to ensure businesses and residents are complying with COVID-19 rules.
Of those charges, 10 were against businesses that did not have a safety plan. Another was for not posting a sign communicating the mandatory mask and physically distancing order.
By-law enforcement officers also charged 11 people for not wearing a face mask inside a business and one for not maintaining physical distancing.
The blitz, which started on November 23, is ongoing.
The officers investigated 21 complaints and carried out pro-active 95 checks at area businesses.