Police say the shooting of a 13-year-old boy outside a Maryland school Monday is related to last week's sniper killings. news_crime_marylandshooting1007_abc.jpg l Sniper Hits Again http://abcnews.go.com/sections/us/videofiles/Video/021007bowie_video.ram 10340070010370 abcnews.gif video.gif http://abcnews.go.com/sections/us/videofiles/Video/021007bowie_video.ram 10340070010371 PLAY lock_icon.gif video.gif lock_icon.gif lock_icon.gif big_headline