Fifth column
Twenty-two of the arrested, including Mashhadi, were executed.
Zainichi Koreans living in Japan, particularly those affiliated with the organization Chongryun (which is itself affiliated with the government of North Korea) are sometimes seen as a "fifth column" by some Japanese, and have been the victims of verbal and physical attacks. These have occurred more frequently since the government of Kim Jong Il acknowledged it had abducted Japanese citizens from Japan and tested ballistic missiles near the waters of and over mainland Japan.
A significant number of Israeli Arabs, who compose approximately 20% of Israel's population, identify more with the Palestinian cause than with the State of Israel or Zionism. As a result, many Israeli Jews, including politicians, rabbis, journalists, and historians, view them (and/or the main Israeli Arab political group, the Joint List) as a fifth column.
Counter-jihad literature has sometimes portrayed Western Muslims as a "fifth column", collectively seeking to destabilize Western nations' identity and values for the benefit of an international Islamic movement intent on the establishment of a caliphate in Western countries. Following the 2015 attack by French-born Muslims on the offices of Charlie Hebdo in Paris, the leader of the UK Independence Party Nigel Farage said that Europe had "a fifth column living within our own countries". In 2001, Dutch politician Pim Fortuyn talked about Muslim immigrants being a "fifth column", on the night he was dismissed as leader of Liveable Netherlands.

In 2022, Russian president Vladimir Putin called Russian citizens who are against the Russian invasion of Ukraine as fifth columnists and "national traitors".
Members of the American and European far-right have been widely described as fifth columnists in light of Russian interference in the 2016 United States presidential election and presidency of Donald Trump and leading up to the 2022 Russian invasion of Ukraine. American conservative journalist Tucker Carlson, in particular, has faced allegations of fifth columnist behavior, especially after he decided to visit Russia and interview Vladimir Putin.
In 2024, following claims that taxpayer funds were improperly given to the UNRWA due to family interests in Gaza during the Israel–Hamas war, Humza Yousaf, the First Minister of Scotland, revealed that he had been subjected to "smears" throughout his political life including allegations he was a "fifth columnist" because of his faith and race.

In popular culture: The title of Ernest Hemingway's only play "The Fifth Column" (1938) is a translation of General Mola's phrase la quinta columna In early 1937, Hemingway had been in Madrid, reporting the war from the loyalist side, and helping make the film The Spanish Earth. He returned to the US to publicize the film and wrote the play, in the Hotel Florida in Madrid, on his next visit to Spain later that year.
In the US, an Australian radio play, The Enemy Within, proved to be very popular, though this popularity was due to the belief that the stories of fifth column activities were based on real events. In December 1940, the Australian censors had the series banned.
British reviewers of Agatha Christie's 1941 novel N or M? used the term to describe the plot's depiction of two British turncoats working on behalf the German government in Britain during World War II.
In Frank Capra's film Meet John Doe (1941), newspaper editor Henry Connell warns the politically naïve protagonist, John Doe, about a businessman's plans to promote his own political ambitions using the apolitical John Doe Clubs. Connell says to John: "Listen, pal, this fifth-column stuff is pretty rotten, isn't it?", identifying the businessman with anti-democratic interests in the United States. When Doe agrees, he adds: "And you'd feel like an awful sucker if you found yourself marching right in the middle of it, wouldn't you?"
Alfred Hitchcock's Saboteur (1942) features Robert Cummings asking for help against "fifth columnists" conspiring to sabotage the American war effort. The film was also released under the name Fifth Column in Dutch (Die van de 5de kolom), Finnish (Viidennen kolonnan mies) and French (Cinquième colonne). Soon the term was being used in popular entertainment.
Several World War II–era animated shorts include the term. Cartoons of Porky Pig asked any "fifth columnists" in the audience to leave the theater immediately. In Looney Tunes' Foney Fables, the narrator of a comic fairy tale described a wolf in sheep's clothing as a "fifth columnist". There was a Merrie Melodies cartoon released in 1943 titled The Fifth-Column Mouse. Comic books also contained references to the fifth column.
Graham Greene, in The Quiet American (1955), uses the phrase "Fifth Column, Third Force, Seventh Day" in the second chapter.
In the 1959 British action film Operation Amsterdam, the term "fifth columnists" is used repeatedly to refer to Nazi-sympathizing members of the Dutch Army.
The V franchise is a set of TV shows, novels and comics about an alien invasion of Earth. A group of aliens opposed to the invasion and assist the human Resistance Movement is called The Fifth Column.
In the episode "Flight Into the Future" from the 1960s TV show Lost In Space, Dr. Smith is referred to as the fifth columnist of the Jupiter 2 expedition. In the first episode, he was a secret agent sent to sabotage the mission who got caught on board at liftoff.
There is an American weekly news podcast called "The Fifth Column", hosted by Kmele Foster, Matt Welch, Michael C. Moynihan, and Anthony Fisher.
Robert A. Heinlein's 1941 story "The Day After Tomorrow", originally titled "Sixth Column", refers to a fictional fifth column that 

destroyed the European democracies from within in the tragic days that led up to the final blackout of European civilization. But this would not be a fifth column of traitors, but a sixth column of patriots whose privilege it would be to destroy the morale of invaders, make them afraid, unsure of themselves.
In Foyle's War, series 2 episode 3, "War Games", one line reads: "It's the Second salvage collection I've missed, they've got me down as a fifth columnist."
In Fallout: London, a total conversion mod for the 2015 Bethesda Softworks action role-playing game Fallout 4, there is a populist faction known as the "5th Column" whose declared aim is to tear down the existing government and rebuild it.  Their propaganda style and black uniforms are a likely reference to the British Union of Fascists, which was founded in 1932 by  Sir Oswald Mosley and banned by the British government in 1940 after the start of World War II amid suspicion that its supporters might form a pro- Nazi "fifth column".

See also: 

Notes: 

References: 

Further reading: 
Mylonas, Harris; Radnitz, Scott (2022). Enemies Within: The Global Politics of Fifth Columns. Oxford University Press. ISBN 978-0-19-762794-5.
The German Fifth Column in Poland. London: Polish Ministry of Info. 1941.
Bilek, Bohumil (1945). Fifth Column at Work. London: Trinity.
Loeffel, Robert (2015). The Fifth Column in World War II: Suspected Subversives in the Pacific War and Australia. Palgrave.
Britt G. The Fifth column is Here / George Britt. New York: Wilfred Funk, Inc., 1940
Lavine H. Fifth column in America / Harold Lavine (1915-). New York: Doubleday, Doran, Incorporated, 1940