Two high school students in New Hampshire were recorded singing a racist rendition of “Jingle Bells,” which promoted the Ku Klux Klan and encouraged killing “all the Blacks.”

According to The Washington Post, the school district is under investigation for the incident, which reportedly took place at Dover High School during a history class on Friday.

Video of the pair singing “KKK, KKK, let’s kill all the Blacks, burn a cross in their front yard and hope they don’t come back,” was partially uploaded to Snapchat before being reposted on YouTube.

Several students can be heard laughing at the inappropriate lyrics. It was reported that the teacher, who has been placed on paid leave, did not stop the performance.

The racist incident follows recent reports of a Black student punching a White student known to wear Nazi uniforms and a group of students in Wisconsin allegedly mimicking the Nazi salute in a prom photo.

District Superintendent William Harbron explained that the class assignment required students to create a jingle inspired by America’s Reconstruction era following the Civil War.

In a letter to the community, Harbron said the school district is “deeply concerned” about the jingle, calling it “an incident of extreme racial insensitivity.”

“What we are much more concerned about is making sure that we use this opportunity to really learn from it and make sure business is done differently, and that all students are respected and regarded — regardless of their background, their race,” Harbron told The Washington Post. “I think that’s more of a concern for us right now.”

Dover High School’s principal is gathering information about the event to help determine if it is cause for punishment. The district has a zero-tolerance discrimination policy that includes both staff and students.

Harbron doesn’t want to prematurely discipline the 11th graders who were doing as they were instructed. He believes Friday’s incident can be used as a teaching moment.

“We don’t only need to deal with what occurred, we need to deal with how to change the culture so something like this does not repeat itself,” he said. “So all students feel safe in the community and feel respected in the community, regardless of your background.”

Dover High has an enrollment of more than 4,000 students, but less than five percent of the student body in the district is of color.