COLLEGE PARK, Md. – At least 12 white supremacists have been arrested on allegations of plotting, threatening or carrying out anti-Semitic attacks in the U.S. since the massacre at a Pittsburgh synagogue nearly one year ago, a Jewish civil rights group reported Sunday. The Anti-Defamation League also counted at least 50 incidents in which white supremacists are accused of targeting Jewish institutions' property since a gunman killed 11 worshippers at the Tree of Life synagogue on Oct.