Officials from a Maryland high school say they are investigating the appearance of flyers on campus with a simple five-word message about white people — "it's OK to be white."

Why is that a problem?

The principal of Montgomery Blair High School, Renay Johnson, explained to a local news station why some were disturbed by the otherwise benign message.

"We are taking this seriously and are investigating this incident," he said. "Our research so far has indicated that this may be part of a concerted national campaign to foment racial and political tension in our school and community."

Where did the flyers appear?

The flyers were discovered outside the school early Wednesday but were taken down before students arrived. The principal sent a letter to the parents informing them about the incident.

Where else were they found?

According to the Washington Post, the flyers were found at other cities as well.

Stickers bearing the same message were discovered Wednesday morning on light poles and electrical boxes in Cambridge, Mass., according to a report in the Boston Globe. Similar signs were found on the campus of Tulane University in New Orleans, and in Rocky River, Ohio.

It appears that the prank was orchestrated by users of the infamous website 4Chan, where various trolling operations are conjured up and implemented by members.