Three Providence groups are planning a peace rally after a string of recent violent attacks in the city. The rally scheduled for Tuesday is being organized by the Children’s Fund, Project: Night Vision, and It’s on Us. Police announced the death this week of 21-year-old Devon Young, who was shot in the head in what Mayor Angel Taveras called a targeted attack. Young is the city’s seventh homicide victim of 2012. There have been more than a dozen shootings in Providence in recent weeks. Among the victims was a 13-year-old boy police say was grazed by a bullet while walking with his brother. Taveras, Public Safety Commissioner Steven Pare, and Police Chief Hugh Clements have been invited to take part in the peace rally.