The comments came two days after a clash in central Malmö that followed a demonstration in support of International Women's Day. While exact details remain unclear, a fight broke out in the area that involved at least one knife and left four people with serious injuries.
The nationalist Party of the Swedes (Svenskarnas Parti – SvP) appeared to take responsibility for the altercation in a statement released on Monday, in which the party confirmed that its members had been involved.
The event has caused a swell of concerned commentary, following as it does the trial against neo-Nazis charged with inciting a riot after the Kärrtorp stand-off between anti-racism demonstrators and members of the Swedish Resistance Movement.
Morgan Johansson, Social Democrat head of the parliamentary committee on judicial affairs, said that the matter was one for Sweden's secret police, Säpo.
"You can't be naive about this, there can be people in these kinds of groups who are prepared to use extreme violence," he told the Expressen newspaper, while adding to other news outlets that there were "many signals" that suggested the extreme right was becoming more organized and was ready to go on the "direct attack".
"You can't rule out that there is a Swedish Anders Breivik among these groups, and if so, it's Säpo's responsibility to get to the bottom of it," he said.
Crime reporter and columnist Oisin Cantwell at the Aftonbladet newspaper went further, tying recent activities on the continent to right-wing movements in Sweden. He said it was high-time that Säpo keep a proper eye on Swedish citizens who have traveled to Ukraine recently.
"At least one of the members of Party of the Swedes that was on the scene in Malmö has visited Ukraine to show support for the extreme right that has taken place in the country's new government," Cantwell wrote.
A spokesperson at Säpo refused to comment on the weekend's incident in Malmö, but told Sveriges Television (SVT) that follow-up was the responsibility of the Malmö police.
Local police said on Monday that they had secured forensic evidence that they hoped would shed light on the incident, but the law enforcers remained tight-lipped about the details.
Officers detained three people following the clash, all in their twenties and all suspected of attempted murder.
"We know too little, we don't know what has occurred or how it's connected. We don't know if it was five, ten, or 30 people involved," Linda Pleym at the Skåne county police told the TT news agency.
The incident prompted further demonstrations on Sunday across the country.