School officials from Wylie, Texas, had to issue an apology on Thursday after a copy of a cartoon that was sent to students was revealed to the public. In the cartoon, police officers were compared to members of the KKK and slave owners.

Fraternal Order of Police (FOP) National Vice President Joe Gamaldi was not amused by the cartoon. He posted a strongly-worded rebuke against the school officials who allowed the image to be sent out to students on Twitter, “This is abhorrent and disgusting, and only further widens the gap between police officers and the youth in our community.”

Officials of the Wylie Independent School District (ISD) said that the cartoon included the lesson that was sent to over 400 students. That lesson was about the Bill of Rights and the right of people to protest. They said that it was a social studies teacher who included the offensive cartoon in the lesson. There was an immediate backlash against it and that forced the school officials to issue an apology.

“We are sorry for any hurt that may have been caused by a lesson that included political cartoons that reflected negatively on LEOs. We value them and will do better. Thanks @GLFOP @TMPALegislative @WyliePD @SachsePD @murphytex for helping us move forward.” The officials also made it clear that the lessons have been canceled and that the cartoon was not part of the resources that are available to teachers.

There was no immediate explanation as to why the teacher included the cartoon in the lesson. Though the lesson has canceled it has caused damage already as students have already seen it. Also, this is just one incident, it is possible that the teachers have been feeding lessons and resources similar to this one for the longest time. There has been no mention of the teacher facing any consequence for using such an offensive material for the lessons.