It is the first time an interim ban has been imposed on a book in New Zealand since the current law was passed 22 years ago. President of the Film and Literature Board of Review Don Mathieson, QC, issued the interim order, banning the book until the full board can consider whether it should be restricted. This overturns a decision by the deputy chief censor Nick McCully that made the book unrestricted last month, which itself overturned a review board order making the book R14. The NZ Post Children's Book Award winning novel, aimed at a teenage audience, contains explicit descriptions of sex and drug use, as well as an offensive term for female genitalia. The decision by Mathieson calls the restriction "a matter of wide public concern," noting that classification of the novel will act as a precedent. "The correct classification of Into the River under the Act will operate as a semi-precedent, and will exert a significant influence upon other decisions portraying teenage sex and drug-taking."

Mathieson, an active Christian, earlier argued for the book to receive an R18 restriction. Conservative lobbying group Family First, who pushed for the review and an R18 restriction, applauded the decision. "We've empowered parents to start expressing their concerns about books more," leader Bob McCoskrie said. "We believe the censor is out of touch with material parents don't want their kids to be reading." McCoskrie supported a wider move to a film-like sticker rating system for books. "We do it for movies so why not books? I think to be honest parents expect this to be happening."

"These books can exert a significant influence. We just think its about age appropriateness." Family First claim the censor has received over 400 letters from concerned parents. Wellington City Libraries manager John Stears found out about the ban on Monday morning. "We're in the process of temporarily withdrawing the items from availability, and are hiding it from our online catalogue currently," he said. "Any copies that are on loan will be captured when they come back."

Wellington High School librarian Jane Shallcrass found the ban ridiculous. "Do they have any idea what is in a school library? It's got some sex in it. For goodness sake, this is life. Kids read this stuff," she said. "I'm stunned. People like Irvine Welsh, that's in school libraries, but they're not banning that," she said. "The people who actually give out awards for books probably know a little bit more about literature than the people censoring it." Into The River won the top prize at the NZ Post Children's Book Awards in 2013. A parental advisory sticker was sent to bookstores after concerns were raised. The censor then classified it as "M" - unrestricted - before the review board partially upheld a Family First appeal and imposed an R14 restriction on the book. This decision was later overturned by the deputy chief censor.

At the time of writing, an ebook version of the book was still available for purchase on Amazon.