Expo's study found that 32 percent of activists it investigated in its report on the Nordic Resistance Movement (Nordiska motståndsrörelsen) had no previously known links to neo-Nazi activity.
“That means that this environment has taken in new individuals. A third of those who were active in 2015 are new recruits,” Expo researcher Jonathan Leman told Swedish radio.
The foundation studied the background of 159 of the most active members of the neo-Nazi group. Of those, 26 percent were charged with violence or weapon offences last year.
According to Expo, more than half of the activists (56 percent) have at some point been convicted of some form of criminal offence. In almost a fourth of the cases the sentence included time in jail, which the foundation states indicates serious crimes.
An estimated 600 far-right demonstrators marched through central Stockholm in November in the organization's biggest march yet. However, the marchers were easily outnumbered by thousands of anti-racists protesting their presence.
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Leman told Swedish radio's news programme Ekot that the organization has recently changed its strategy, by among other things deciding to found a political party, which he said explains its new members.
“I think it partly has to do with the fact that the threshold for becoming active in this organization has been lowered. They want to attract people in a broader way than before,” he said, arguing for more in-depth scrutiny of these groups.
“Knowledge of how today's Nazi movements look is needed, it is especially important when it comes to the Nordic Resistance Movement because they are dominating within the white power environment,” said Leman.
Expo's annual report in May found that Swedish neo-Nazi groups were less active than before in 2015, but that the Nordic Resistance Movement was growing. It said at the time that this was primarily a result of other neo-Nazi organizations closing down.