A civil rights group is investigating reports of a fake mailer circulating in College Station that warns of a $500 fine for displaying signs supporting U.S. Senate candidate Beto O'Rourke.

A civil rights group is investigating reports of a fake mailer circulating in College Station that warns of a $500 fine for displaying signs supporting U.S. Senate candidate Beto O'Rourke.

The letter, recently obtained by the Texas Civil Rights Project, features a "CITATION WARNING," "quick facts about" O'Rourke and a "'BETO' REALITY CHECK" that includes the comments "NOT HISPANIC," "FELONY ARREST RECORD," "INSIDER TRADING VIOLATIONS," "FATHER'S DRUG SCANDAL" and "FAMILY BUSINESS FEDERALLY PROSECUTED," according to images of the letter the organization shared on social media Tuesday. The letter appears to end with "These issues have not been effectively reported to Texas voters."

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The envelope for the letter had a fake Austin return address, the organization's voting rights legal director, Beth Stevens, told the American-Statesman. It appears the letter was processed and sent through a post office in North Houston, she said.

"It's absolutely a voter suppression tactic," Stevens told the Statesman Tuesday.

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A spokeswoman for the Cruz campaign said it wasn't responsible for the mailer. O'Rourke's campaign declined to comment on the report.

Stevens said the organization has contacted the Texas secretary of state's office and might work with a law enforcement agency on the matter.

Texas residents can't be fined for placing political signs on their own property, and "materials suggesting otherwise are fake and should be ignored," the secretary of state's office said in a statement spokesman Sam Taylor shared with the Statesman Wednesday.

"In Texas, you cannot face penalties for electioneering unless you are doing so within 100 feet of the entrance to a polling place during the early voting period or on Election Day," the agency spells out. "Voters need to remain vigilant and continue to report false and misleading materials purporting to be from an official government agency to the media and to the Texas Ethics Commission.”