There are a lot of gaps in this story. Are handguns involved,and if so there are strict regulations on the acquisition and storage of these guns and the transportation of these weapons. They must be locked, in a secure location and the ammunition stored in a separate location. Rifles and shotguns  have similar restrictions although rules are different for transportation and actual use. The study talks about injuries from firearms which suggests the illegal use of handguns as high powered rifles and shotguns will more often involve death than injuries. The papers are often filled with stories of gunshot injuries to youths, usually arms or legs, this suggests gangs. Simple too little information in this story,.