An 18-year-old Glenburn man has been arrested after, police say, he hit a teenager with a hammer while the two were in a car on Ohio Street.Lawrence Dipietro appeared in court Friday, charged with aggravated assault.Police say there were several people in the car Wednesday night when a 17-year-old was injured. The teen escaped and was taken to the hospital, where he was treated for his injuries and released.Friday, Dipietrio’s friends gathered at the courthouse. They say the incident stems from an ongoing feud between two groups of young people in Bangor, a dispute that was also linked to a fatal shooting on Cumberland Street in January.Friends say during Wednesday night’s incident, Dipietro was acting in self-defense.”I’m more surprised it was Lawrence than anybody else, because Lawrence is in school still,” says Michael Tracy. “He’s a good kid, does sports and everything. I don’t think he deserves this,” says Hannah Bard.Bail for Dipietro was set at one-thousand dollars. We’re told he had no criminal record.Police are still investigating.