(Portland, OR)  --  Portland police say more than a dozen people were arrested yesterday during a protest by a group that pledged "unrest" unless Police Chief Michael Marshman was fired.  Members of the group converged yesterday afternoon on Pioneer Courthouse Square and began blocking traffic and TriMet transports.  Police arrested six demonstrators minutes later, and that number eventually grew to 14.  KATU-TV reports most of those arrested are facing disorderly-conduct charges.