Three people in the Red River High School student section wear Ku Klux Klan-style white robes and hoods during a semifinal game Friday in the North Dakota Boys Hockey Tournament at Ralph Engelstad Arena in Grand Forks, N.D. Mark Rerick, the Grand Forks Public Schools' athletics director, said he asked administrators from the Grand Forks high school to investigate the incident after the photo appeared on the social network site Twitter.