A South Carolina high school will have extra security measures in place when students return from Labor Day weekend, after Jewish and Muslim students were threatened on social media.

A student reported the “extremely vulgar” threats toward Jewish and Muslim students at Byrnes High School to the Spartanburg County Sherriff’s Office Friday night, according to local media.

The threats, which appeared on Facebook, warned the high school would be attacked Tuesday and included pictures of a person in a gas mask and a knife with a swastika on the handle, according to the Spartanburg Herald-Journal. The sheriff’s office took screenshots of the posts.

Law enforcement told local media they would patrol the school over the weekend and make sweeps of the campus. There are 12 schools in the district, and all will have additional security.

“I was very alarmed when I saw the post and how vile some of the language was and how direct the threats were, and not only against our students but families of our students, and in today’s culture, the discourse that is going on and what’s happened in our own country and in other countries, we’re taking it very seriously,” Dr. Scott Turner, the district’s superintendent, said Saturday night during a news conference, according to reports.

“I want to ensure our parents and community that we are taking these threats extremely seriously, and are doing everything possible to make sure our campuses are secure. We are working with law enforcement to ensure the individual who made these threats is found,” Turner also said in a statement.

All parents in the district were called and notified of the incident Saturday afternoon, the Spartanburg Herald-Journal reported.