US novelist Dan Brown’s best-selling thriller, The Da Vinci Code was banned in Istanbul’s Silivri prison under Turkey’s post-coup emergency measures, according to the main opposition Republican Peoples’ Party (CHP) deputy Baris Yarkadas.

“Silivri Prison’s management told the family members of a prisoner that they would not let in The Da Vinci Code…I suspect that they got nervous when they saw the “code” in the title. There is no explanation otherwise,” Yarkadas told Birgun newspaper.

“[The Turkish translation of] the book in question was published by Altin Kitap [Golden Books publishing house]. The management said they are not allowing the books by Altin Kitap into prison. They probably established imaginary links between Altin Kitap and FETO’s Altin Nesil [Golden Generation]. This is an example of paranoia and of the eclipse of reason. I believe the Justice Minister Abdulhamit Gul will resolve this issue, otherwise it is indeed becoming a matter of interest for Dan Brown.

Golden Generation refers to the Gulen movement’s alleged vision of “young people who are educated in science, but have Muslim ethics.”

Turkish government accuses the Gulen movement of masterminding the July 15, 2016 coup attempt and calls it FETO, short for the alleged Fethullahist Terrorist Organization, while the latter denies involvement. Some opposition groups also embrace the controversial buzzword, FETO although the movement harshly reject terrorism.

Prisones and post-coup arrestees in particular were earlier denied access to the books published by the publishing houses that that government had shut down under emergency rules.

At least 30 publishing houses were closed down since the failed coup while some 139,141 copies of books were removed from 1,142 public libraries across Turkey as part of the government’s post-coup crackdown, according to the Culture and Tourism Ministry data.

Last year, a mathematics textbook was banned at a school just because it features Fethullah Gülen’s initials in a practice question that reads: ‘… from point F to point G ….’

Turkey’s Education Ministry destroyed at least 1.8 million copies of textbooks that mention the word “Pennsylvania,” or that include texts from government-targeted journalists, Birgün daily reported in December, 2016. The objectionable textbook for sixth graders reportedly refers to American author James Michener, who mentioned Pennsylvania as his place of birth. Michener’s text was censored only because Gülen lives in that same US state.

Turkish police have, on multiple occasions, displayed seized copies of Gülen’s books as terror evidence over the past year.

Also, license plates including the letters “FG” were removed from vehicles belonging to the Denizli Courthouse in August 2016.