( CNN ) -- Tens of thousands of protesters unhappy with planned tuition hikes in Quebec took to the streets Tuesday afternoon in Montreal to mark 100 days of demonstrations . After a weekend of clashes , tension at first subsided because organizers of the downtown rally provided an itinerary in advance , as required by an emergency law passed late last week , police said . Still , the protesters , many wearing red , split into three groups , with only one column following the prescribed route . Montreal Police Cmdr . Ian Lafreniere said there had been no arrests in the afternoon protest . Police were unable to detain suspected anarchists who threw rocks and broke bank windows because they ran toward another group of protesters , he said . `` Luckily it 's been raining , '' he told CNN . But some protesters wearing masks threw objects at police officers in another march Tuesday night , said police spokesman Daniel Fortier . Six people were arrested . Police had warned demonstrators three times that their protest was illegal , Fortier said . Police would not provide crowd estimates . Tuesday 's protest was intended to denounce tuition increases and Bill 78 , which requires organizers of a demonstration with more than 50 participants to provide written details and the route of the event eight hours in advance . `` The exercise of democracy has to be done without disruption to ensure that no unfortunate event take place , '' police said . CLASSE , considered the most militant of the province 's three main student associations , has said it will continue to protest without giving police an approved itinerary , according to CNN Canada affiliate CTV . `` We are witnessing the biggest act of civil disobedience in Canadian history , '' read one post on a CLASSE Twitter page . `` We have a rendezvous with history , and we wo n't miss it , '' read another . Tuesday 's march was planned by a coalition of 140 community groups and unions , some of which said they 're heeding the new legislation . At least 300 people were arrested and 20 were injured in Montreal during weekend clashes between police and protesters , according to CTV . The movement began after a proposed tuition hike of $ 1,625 , which would be implemented over several years . Lafreniere said police have made about 1,000 arrests since the protests began . `` It 's day by day . It 's a peaceful city , normally , '' he said .
NEW : Six arrested in evening protests . Tens of thousands of students protest in Montreal . The students in Quebec province are unhappy about planned tuition hikes . Tuesday 's protests follow weekend clashes in which 300 were arrested .