The New Jersey chapter of the ACLU has filed a lawsuit against a school for suspending former students who posted photos of guns on Snapchat.

The ACLU says that Lacey Township High School officials infringed on the student’s First Amendment rights for suspending the two students in March 2018 after they posted the photos from an off-campus shooting range outside of school hours.

The students, Cody Conroy and a student only identified as H.S. due to his age at the time of the suspension, were at a shooting range owned by one of Conroy’s relatives. The photos posted on Snapchat were of legally owned firearms featuring the captions “hot stuff” and “If there’s ever a zombie apocalypse, you know where to go.”

According to the ACLU, another student saw the photos and reportedly became nervous to attend school and told a parent who told school officials.

The students maintain that there were no threats made against the school or a particular student. They say that because the photos were taken outside of school and school hours, the school had no right to discipline them.

The ACLU says that Conroy and H.S. seek several changes from the school district in order to “bolster the speech of students.”

The lawsuit was filed Wednesday.