Who are the followers of the Black bloc’s tactics in Brazil?

On the link below, professor Rafael Alcadipani summarizes final considerations of an on-going empirical-qualitative study. It deals with the protesters and demonstrators who adopt the black bloc’s tactics. Check it out: http://www1.folha.uol.com.br/opiniao/2013/08/1327177-rafael-alcadipani-para-entender-a-violencia.shtml