An Illinois high school is spending thousands to reprint its yearbooks after several photos of students throwing up a white nationalism hand sign were discovered in the final copies.

School administrators at Oak Park and River Forest High School found the photos after yearbooks came back from the printer, reports CBS Chicago. Students in 18 photos were seen displaying an upside-down okay sign, typically associated with white nationalism.

“The sign has more recently become associated with white nationalism,” superintendent Joylynn Pruitt-Adams wrote in an email to parents. “The photos in question, as well as all the other club team/photos in which students are striking poses and making gestures, will be replaced with the straight-forward group shots.”

The school considered placing stickers over the signs but decided against it because they would “place a cloud of suspicion over all the students in those photos, regardless of whether they used the sign or not.”

The photos were taken in October 2018, before the school knew about the connotation of the gesture. It will cost the district $53,794 to reprint the books, according to The Chicago Sun-Times. The students will receive blank booklets to use if they wish to collect signatures from their classmates.

The students who made the gestures have not been disciplined.

“Those pages were reviewed and shipped to the printer in early December, before the gesture was widely known to have any association with white nationalism,” Pruitt-Adams said in the letter. “I want to be clear that we are not making any presumptions about students’ intent in using the gesture.”

It will take about four weeks for the student body to receive the edited yearbooks.