A group of approximately 100 men clad in black masks descended upon a Stockholm train station on Friday night and began physically attacking young immigrants, Swedish police told BuzzFeed News.
According to a statement released by Swedish police, the men intended to "expose unaccompanied refugee children to crime," and were seen passing out flyers with negative messages about immigrants in Sweden shortly before the incident.
Video footage of the assault, which appeared on the website of local news outlet Aftonbladet, shows the group of men running through the halls of the train station yelling. At one point, a man slaps a long, thin object against a pillar.
None of the targets of the attack had to be treated for serious injuries, police spokesperson Albin Naëverberg told BuzzFeed News.
Four suspects arrested have since been released from custody.
The incident took place near Sergels torg, the city's biggest public square, around 8:30 p.m. local time, according to Naëverberg.
Naëverberg said that a majority of the assailants — men between the ages of 15 and 30 — did not carry weapons, although one wore what he described as brass knuckles.
Around 50 officers arrived at the scene. The man wearing brass knuckles clashed with a Swedish police officer who had darker skin, Naëverberg said. He was arrested and released, but will appear in court at a later date.
Several outlets have reported a possible affiliation between the masked group and a notorious Swedish football gang, but police have not confirmed the connection.
Naëverberg said that the attack came after a few weeks of relative calm, but acknowledged that there had been incidents in which young immigrants were targeted before.
Tensions between Swedish nationals and immigrants have increased since a 22-year-old Swedish aid worker was stabbed to death by a 15-year-old boy at an asylum center on Jan. 26.
Two days later, the government announced it could deport as many as 80,000 asylum-seekers in the coming years.
Sweden, like many other European nations, has been inundated by tens of thousands of people arriving from the Middle East and Africa, fleeing war and poverty.
The neo-Nazi group Swedish Resistance Movement issued a statement after the attack, according to The Local, an English-language, Swedish news source.
The group claimed the men had "cleaned up criminal immigrants from North Africa that are housed in the area around the central station."