Richard Jomshof, one of the so-called 'gang of four' who took over the Sweden Democrats in 1995 and turned it into a party capable of entering parliament, made the attack in a post on X, in which he showed an image of Anders Lindberg, political editor of the Aftonbladet newspaper next to Quisling.

"The man on the left is Quisling. The man on the right is a quisling," he wrote.

As the post generated increasing outrage, Lindberg said he interpreted it as a threat.

"It cross all boundaries. The shot Quisling, as he very well knows. I do not like the fact that leading politicians are calling journalists traitors to the nation."

Magdalena Andersson, leader of the opposition Social Democrats, called Jomshof's statement "deeply unSwedish".

"This is clearly a party which works actively to silence critical voice. That's not how we behave in Sweden."

Jomshof hit back, arguing that Lindberg himself had back in 2018 compared Prime Minister Ulf Kristersson to Franz von Papen, the German conservative who brought Adolf Hitler and the Nazi power to party in their first coalition.

"If the term 'von Papen' can be used to describe Kristersson, the term 'Quisling' can very well be used to describe Lindberg. However, I do not write that Lindberg is Quisling but a quisling," he wrote.

"Even Magdalena Andersson is a quisling," he continued. "They all grovel in front of the Islamists whose goal is to take our democracy and our country from us."

Jimmie Åkesson, leader of the Sweden Democrats, acknowledged that Jomshof had expressed himself provocatively, but accused the opposition parties of feigning their shock.

“Hyperbole tends to obscure the core of the message. And public debate is always best served by factuality and civility. That said, the term ‘crocodile tears’ has never been more apt,” he wrote on X.

Kristersson himself said that the statement was "distasteful and indecent".

"You simply don’t speak that way. You can have a tough political debate and discuss difficult issues, but you have to be able to separate the issue from the person. Frankly, that applies to both Jomshof and Aftonbladet."