An Illinois high school yearbook that ran a headline “No one ugly allowed!” on its cheerleading team page ignited backlash on social media, prompting the school principal on Tuesday to apologize.

An article in the Oswego High School’s yearbook page described the steps the cheerleading squad took to “convey confidence,” and the headline—written in bright orange and in all caps-- was part of a song the coaches selected to “hype us up” before competitions, The Aurora Beacon-News reported.

One parent of a former student told the paper that she is “shocked, ashamed and embarrassed.”

“No matter the context, the title is negative, irresponsible and thoughtless,” the parent said.

Social media comments called the headline “disgusting” and a bad message to girls, The Beacon-News reported.

Mike Wayne, the school’s principal, apologized in a statement.

“The headline of the article is inappropriate and should have been recognized and removed during the editing process,” Wayne said. “While the headline quotes a line in a song, and was not intended to come across as offensive, it has, and we sincerely apologize.”

Wayne said the school would work to review the yearbook with "a more sensitive eye."