Since Swedish police were accused yesterday of covering up years of sex attacks by recent immigrants at a music festival, one Afghan teenager has already been arrested and Sweden’s liberal, pro mass migration prime minister has slammed the “double betrayal” of women by police.

It has also emerged that Stockholm Council and the festival organisers identified the sex mob phenomenon two years ago, but claimed it would have been “irresponsible” to have spoken out.

Furthermore, the Swedish paper which broke the story yesterday is alleged to have been tipped off six months ago, and may never have published the information were it not for the Cologne sex attack cover-up scandal.

Quoting sources within the force, Dagens Nyheter (DN) claimed Stockholm Police consciously avoid reporting on issues which can be tied to perpetrators of a foreign background, because they fear it may help right-wing politicians.

The festival took place a month before general elections in which the anti-mass migration Sweden Democrats came third.

Björn Söder, one of the party’s MPs, told Expressen: “It is a scandal without equal. Could this have happened at several locations in the country, but they don’t tell you certain things because it could ‘play into the hands’ [of the Sweden Democrats]’?”]

Migrant sex gangs are alleged to have been roaming the Sthlm music festival for 12 to 17-year-olds for the past two summers. “These are so-called refugee youths, specifically from Afghanistan. Several of the gang were arrested for sexual molestation,” one leaked police memo read, indicating that they were well aware of the situation.

Just like in Cologne, however (where the local force released a statement claiming New Year’s had “passed off peacefully”), the Swedish police’s report of the festival was resoundingly positive, and made no mention of sexual assault.

Yet there were in fact 38 reports of rape and sexual assault made in 2014 and 2015, according to the police yesterday, who only released the information on Monday after the DN newspaper suggested a cover up.

During a single night, police and security guards had to intervene against 90 young men taking part in the abuse, one eyewitness told the paper.

“We should certainly have written and told people about this, no doubt. Why it did not happen I do not know,” Varg Gyllander, a police press spokesperson, confessed yesterday.

“Just became aware of DNs data tonight. Promise that the matter will be investigated”, Sweden’s National Police Commissioner Dan Eliasson tweeted.

Swedish police still won’t specify how many refugees were linked to the crimes, however DN suggested that 50 refugees from Afghanistan, who had come to Sweden without their parents, were suspects.

Last night, Prime Minister Stefan Löfven waded in on the emerging scandal. He said it amounted to a “double betrayal” since no one was prosecuted for the crimes and the police did not make the crimes public.

Just days after DN reported on the police cover-up, however, the paper itself has been accused of covering up and ignoring the story.

A psychologist has claimed she tipped off the newspaper about groping claims at the festival six months ago, but the paper chose not to follow up the story.

Furthermore, an inside source told the Nyheteridag news site the DN editor was not interested in the story, because she though it may have been fabricated by supporters of the Sweden Democrats or might whip up anti immigration sentiment.

The DN editor has since admitted that they were tipped off, but claimed they could not publish anything because the police would not confirm the reports.

“We took it very seriously, had contact with the source and tried to move forward with the tip, but failed to get it confirmed”, he claimed in an editorial.

The festival organisers themselves have now said they picked up on rumors of the new phenomenon back in 2014, said Roger Mr. Ticoalu, head of events at the Stockholm city administration.

“It was a modus operandi that we had never seen before: large groups of young men who surround girls and molest them,” he told the Guardian.

“In the cases where we were able to apprehend suspects, they were with a foreign background, newly arrived refugees aged 17-20, who had come to Sweden without their families.”

However he said festival organisers say they did not have enough facts at the time to say anything definitive, and it would have been “totally irresponsible on our side to make anything public”.