tag-banging
n.— «Once benign, even romanticized, tagging has turned into a violent competition for territory, complete with shootings, fights and stabbings normally associated with street gangs, according to police and deputies who have seen tagging crews grow increasingly violent over the past three years. They even have a name for the phenomenon: “tag-banging.”» —“Tagger gangs getting violent” by Sandy Mazza Whittier Daily News (California) Nov. 12, 2006. (source: Double-Tongued Dictionary)