A Facebook page called "We who support the vigilantes" and which seems to offer praise to members of Friday night's mob has published a picture of what is presumably the flyer handed out. It says "Police have clearly shown that they lack the means to repress their (North African "street kids") progress, and now we see no other alternative than to hand out the punishment they deserve ourselves."
Christer Birgersson, a superintendent from the Stockholm Police speaking with Radio Sweden about the dedicated police detail, said the police were looking at the flyers.
"We have taken a few of them... to do a criminal investigation (to see) if there is some crime committed in the texts that is written down on those flyers," he said.
Birgersson stressed that the police were not establishing a new, permanent unit for counteracting far-right extremism. Rather, the police were investigating whether the demonstrations represented a trend or a one-time event, and they were assigning personnel and resources to maintain a presence in the public spaces where such demonstrations might occur.
"We have police offers temporarily assigned to work at the places in Stockholm city where this could happen again," he said.
Birgersson described the events Friday. He said the group of masked men walked down the street chanting. The police had caught wind of a possible demonstration and so were present while the men walked the street. One undercover officer was struck and the face by one of the masked men who was promptly arrested.
But the police had not received any reports that anyone was chased or beaten. Birgersson encouraged anyone with any information about harassment or violence to report it to the police.
The police see a link between the events Friday and an anti-refugee demonstration at Norrmalmstorg the following day, which resulted in several assaults, writes news agency TT. A total of 14 people have been detained in investigations into conspiracy to commit gross assault, and violence against a public servant.
Earlier Birgersson told TT that the police would aim to "get a picture of what happened and who the different actors are. Is it a trend, or a one off?" He added that, at the same time, the police have an "operative resource" that will work to prevent things like this from happening in the future.
Police will be roving around Stockholm, particularly in central parts of the city, in the areas where they believe mobs can strike, but the police did not want to say how many officers would be on the beat.