A North Dakota high school principal said the school is taking what he described as appropriate action against three students who were photographed wearing Ku Klux Klan-style robes and hoods at a state semifinal hockey game.

The three students, who attend Red River High School in Grand Forks, were photographed sitting in the stands Friday night to watch their school face off against the team from Davies High School in Fargo.

Kristopher Arason, Red River's principal, told The Associated Press that a school investigation determined the students had put on the garb after the first goal and wore it for 30 seconds to a minute.

"We, as a school, are extremely disappointed with the behavior of these three students," Arason said in a statement. "This behavior is not a representation of our school or student body."

A photograph showing the three hooded figures, surrounded by fellow students who were all wearing white, was posted on Twitter by Shane Schuster, who had been a spectator at the game.

"I guess the red river highschoolers are racist?" he tweeted.

As of Sunday afternoon, the photo had been retweeted 97 times, with many people expressing their outrage at the stunt.

Arason declined to discuss what disciplinary action, if any, the school would be taking against the students.

Red River won the match with a score of 2-0.