Controversial right-wing pundit Glenn Beck has compared the victims of the Norway massacre to members of the Hitler Youth in the 1920s and 1930s.
Mr Beck, who last year was criticised for suggesting Holocaust survivor George Soros collaborated with the Nazis, made the comments on his popular radio programme.
He noted that the attacker had targeted young and engaged members of the Norwegian Labour party as they attended an annual summer retreat.
"It sounds a little like the Hitler Youth," he said. "I mean who sends their kids to a political camp?".
At its peak, the Hitler Youth had some eight million members. Established in 1922, it served as a training point for young Germans, who were taught ideas of Aryan supremacy at weekly meetings, larger rallies and schools set up for the purpose.
Although many joined voluntarily, it remains a subject of debate as to how many were conscripted against their wishes.
Pope Benedict, who was 12 when the Second World War began, was technically a member, but always denied that he chose to join it.
Mr Beck's comments were criticised as "a new low" by Torbjorn Eriksen, a former spokesman for Norwegian Prime Minister Jens Stoltenberg.