(CNN) The banners have been hung from highway overpasses and rooftops in several states across the country.

They're not discreet. And their creators -- usually white supremacist groups who proudly put their name and logo on the banners -- are not mincing words or using euphemisms, according to the Anti-Defamation League.

"WHITE FAMILIES MATTER." "FOR RACE AND NATION." "'DIVERSITY' IS A CODE WORD FOR GENOCIDE." "UNjew HUMANITY."

These are just some of the anti-immigration, racist or anti-Semitic statements displayed on the banners, and the underlying message is clear: If you're nonwhite and were not born in America, these groups don't want you here.

The banners have appeared more frequently in the past year, according to a report released Thursday by the Anti-Defamation League's Center on Extremism. It has counted at least 72 highly visible and disturbing messages deployed by mostly white supremacist groups since May 2017, a figure that "marks an unprecedented trend," the group said in a blog post labeled "New White Supremacist Tactic: Banners of Hate."

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