In a segment on Fox News's “The O'Reilly Factor” that aired Thursday, host Bill O'Reilly spoke with two Swedish nationals about allegations that Sweden had become a more dangerous place in recent years because of immigration.

One guest, Swedish journalist Anne-Sofie Naslund of the Expressen newspaper, pushed back against O'Reilly's comments, suggesting that her country was far safer than it was being presented.

However, the next guest disagreed.

Nils Bildt, billed as a “Swedish defense and national security adviser” by Fox News, told O'Reilly that Naslund was “rather incorrect” and that there had been big problems with integrating immigrants into Swedish society. “These things are not being openly and honestly discussed,” Bildt said.

It was only a brief segment, but it quickly caused controversy back in Sweden, where reporters and experts suggested that Bildt was unknown within the Swedish national security world.

The Dagens Nyheter newspaper reported Friday that neither the Swedish armed forces nor the Foreign Ministry had heard of Bildt. Johan Wiktorin, a fellow at the Royal Swedish Academy of War Sciences, took to Twitter to suggest he had not heard of Bildt either.

On Twitter, a number of Swedes mocked Fox News's decision to book Bildt.

But who is Nils Bildt? Dagens Nyheter reported that Bildt had in fact emigrated from Sweden in 1994 and that he was originally named Nils Tolling. The newspaper also said Bildt had been convicted of a violent offense while living in Virginia and was given a one-year prison sentence in 2014.

Reached via email, Bildt initially said that he did not dispute anything in the Dagens Nyheter report, though he noted that he had not chosen the title with which he was attributed by Fox News. “I made clear that I am an independent analyst,” Bildt said. Later, he followed up to dispute the claim he had served time in prison.

“Had I spent a year in prison, I would think I would remember it,” Bildt said.

The surname Bildt is well-known in Swedish political circles due to Carl Bildt, the former Swedish prime minister and Swedish foreign minister. Nils Bildt said that he was related to Carl Bildt, who he described as a “most decent and good man.” However, when contacted by WorldViews, Carl Bildt noted that his brother, a successful Swedish entrepreneur who is also called Nils, was “highly irritated” when he heard Nils Tolling had began using the surname Bildt. Carl Bildt suggested that the former Nils Tolling had been “trying to use the name to gain favors.”

The Bildt who Fox News interviewed is listed as one of the founding partners of Modus World LLC. The company, which says it is based in Washington, Brussels and Tokyo, offers a variety of consulting services, including the “operations and management of possible kidnap and ransom situations,” according to its website, and reports in the Japanese media suggest Bildt was involved a number of hostage negotiations involving Japanese citizens.

David Tabacoff, executive producer of “The O'Reilly Factor,” defended the decision to book Bildt. “Our booker made numerous inquiries and spoke to people who recommended Nils Bildt and after pre-interviewing him and reviewing his bio, we agreed that he would make a good guest for the topic that evening,” Tabacoff said in a statement. (Fox News later said O'Reilly would address the matter on his Monday show.)

However, Bildt's low profile made him a surprising choice, according to Swedish experts. Robert Egnell, a professor at Swedish Defence University, told WorldViews that he did know Bildt, but it was only by chance: The pair had studied together at King’s College London in 2002.

Egnell said that Bildt had left the program early and moved to Japan, after which they had gradually lost touch. “He is in not in any way a known quantity in Sweden and has never been part of the Swedish debate,” Egnell said in an email “He has not lived in Sweden for a very long time and no one within the Swedish security community (which is not a very big pond) seems to know him.”

Fox News's coverage of Sweden has become a subject of debate over the past week, after President Trump referred to “what’s happening” in the country during a rally in Florida last weekend. Swedish experts were confused by the comments, but Trump later clarified he had been referring to a segment with filmmaker Ami Horowitz that had aired on Fox News Channel's “Tucker Carlson Tonight.”

At a Florida rally on Feb. 18, President Trump listed several countries with large numbers of refugees that were recently struck by terror attacks. "You look at what's happening last night in Sweden," Trump said. Swedish authorities are not aware of any such incident that night. (Reuters)

Horowitz's film had suggested a link between refugees and increased crime rates in Sweden, but Swedish experts say he oversimplified the problem, and two policemen interviewed by the filmmaker said they had been misrepresented by him.

Speaking to Dagens Nyheter, security expert Wiktorin had suggested Bildt's interview was a “disturbing trend” in U.S. media where Sweden is presented as a “problem country.”

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