“The atmosphere was very unpleasant,” principal Martin Augustsson told Swedish news wire TT on Tuesday.
Peder Skrivare school head Augustsson, who had organized the Monday evening lecture with Holocaust survivor and author Mietek Grocher, told how six to eight men between 25 and 30 years old walked into the lecture room half an hour into the talk on Monday evening.
“Two wore bomber jackets and one had a shaved head. They stomped in in a row, exactly the same distance from each other. They sat down at the front and one of them turned around and took pictures of the audience,” a member of the audience, who preferred to remain anonymous, told regional paper Hallands Nyheter.
Grocher, 88, continued his lecture without giving any attention to the neo-Nazi group, according to Augustsson, who alerted the police to the men's presence.
“Considering the theme of the lecture I understood that they didn't have any real business there, but were there only to cause a stir,” the principal of the secondary school told TT.
“The unpleasant atmosphere spread and many changed their seats and some probably left. They didn't want to sit anywhere near them,” he added.
Police said that the men remained calm and seated when they arrived at the scene and left after around half an hour.
“They did not interfere with anything, and in that case we don't act. But we remained on site because the audience was unnerved. We noted that a number of individuals were not necessarily there to listen to the message, but they still had the right to be in the room,” Andreas Eriksson of the regional Halland police told Hallands Nyheter.
“I have worked as a police officer in Halland for 13 years and have never experienced anything similar,” he added.
The talk was given to members of the public and was part of a series of three lectures, one of which was being held in front of school pupils on Tuesday morning.
“I am used to this kind of thing, it's happened several times before. I don't feel afraid, but it's unpleasant. When I came to Sweden I never thought I would experience neo-Nazism, but here they are now,” Grocher told Hallands Nyheter.
Neo-Nazi organization the Swedish Resistance Movement claimed on their website on Monday night that they had been present at the lecture in Varberg.
Sweden's far-right groups are declining in numbers, but their activity has been growing in intensity, a report by Swedish anti-racist foundation Expo suggested in March. In total, the number of neo-Nazi activities rose by 23 percent in 2014, from 2,334 in 2013 to 2,864 last year.