December 26, 2013 10:48 am Bieber Tweets Leave Fans Confused 19-year-old pop star Justin Bieber took to twitter to announce his retirement. But additional tweets left fans wondering exactly what that means. US & World Videos 1:36 Arizona Senate repeals 1864 abortion ban 2:15 Heavily-camouflaged minors charged after ‘assassins' game at Old Lyme school 2:40 7th grader brought gun to school in Hartford: police 1:40 Democrats say Big Oil misled public for decades about climate change 1:36 A student brought a gun to middle school in Hartford: police