A Northern California middle school is receiving national attention after a substitute secretary sent out a newsletter to the school’s community that had a racist cartoon.

According to California’s Contra Costa Times , officials from Sequoia Middle School in Pleasant Hills said that the image was mistakenly embedded in their newsletter that was issued earlier this month.

The publication, which features school announcements and current events, also featured a Black “Peanuts”-style cartoon character with a noose around his neck. The words “White pride” also appeared at the top of the image.

Days later, the school’s principal Connie Cirimeli issued an email to parents, apologizing for the incident.

“I am reaching out to apologize to our school community,” the email read, according to the BayAreaNewsTalk blog. “This graphic was attached in error and without my knowledge or consent. Please accept our sincere apology for any offense this has caused. I assure you that this graphic does not represent our school’s values. Thank you for understanding.”

After investigating the incident, school officials realized the image was actually photographic evidence that was used by the police after someone had defaced a campus mural in 2008.

Cirimeli said the substitute secretary did not examine the image thoroughly as she worked on the newsletter and did not follow office protocol as she submitted the publication without having it proofread by another employee.

“It is office protocol that any publication distribution of information be proofread by a second employee and given to the office manager for final approval before publishing,” Cirimeli said in a letter, according to the Contra Costa Times.

She added that in the future, school crime evidence will be stored digitally on secured computers and will only be available to administrators. Moreover, substitute staffers will not have access to the school-wide emailing system.

As for the substitute secretary involved in the incident, Cirimeli said “appropriate personnel action” will be taken.