The aim of this study is to determine the frequency of violent and criminal Twitter communications among gang-affiliated individuals in Detroit, Michigan. We analyzed 8.5 million Detroit gang members' tweets from January 2013 to March 2014 to assess whether they contained Internet banging-related keywords. We found that 4.7% of gang-affiliated user tweets consisted of terms related to violence and crime. Violence and crime-related communications fell into 4 main categories: (a) beefing (267,221 tweets), (b) grief (79,971 tweets), (c) guns (3,551 tweets), and (d) substance use and distribution (47,638 tweets). Patterns in violent and criminal communication that may be helpful in predicting future gang activities were identified, which has implications for violence prevention research, practice, and policy.