Wahlberg has been in trouble 20–25 times with the Boston Police Department in his youth. By the age of 13, Wahlberg had developed an addiction to cocaine and other substances.[7][8] At 15, he harassed a group of black school children on a field trip by throwing rocks and shouting racial epithets.[9] When he was 16, Wahlberg approached a middle-aged Vietnamese man on the street and, using a large wooden stick, knocked him unconscious (while calling him "Vietnam fucking shit"). He also attacked another Vietnamese man, leaving him permanently blind in one eye.