Two alleged “narco-banners” that surfaced online this month, which warned Americans to stay out of Mexico’s Los Cabos region, have sparked concern about cartel intimidation tactics, even as local officials insist the signs never existed.

The purported messages, signed by a faction of the Sinaloa Cartel known as La Chapiza, threatened violence against U.S. citizens living in or visiting the popular tourist destination. Photos of the banners circulated widely across social media, though authorities in Baja California Sur say investigators found no trace of them.

Wyoming County, Pennsylvania District Attorney Joe Peters, who served in the White House’s drug czar office during the Bill Clinton and George W. Bush administrations, told Fox News Digital that whether or not the Cabo banners were physically verified, the tactic itself is consistent with decades of cartel “narco-terrorism.”

“When you’re dealing with a cartel that’s that serious and sophisticated and right at our back door, we have to take it seriously,” Peters said. “It’s a shot over the bow to both governments. They rule by threat and intimidation – the same way the mafia did.”

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Public “narco -anners,” or narcomantas, have long been used by Mexican cartels as propaganda tools, with the large signs draped across bridges or hung in public plazas to issue threats, claim territory or taunt rivals.

Peters said reports of such banners should be taken seriously given the proximity to America’s borders.

“When you’re dealing with a cartel that serious and that close to our border, we have to take it seriously. Add to that the number of Americans traveling to Latin America for business or pleasure — it’s a ready stock of potential victims for extortion,” he said.

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Peters, who served in senior roles in the White House’s Office of National Drug Control Policy under Presidents Clinton and George W. Bush, said the current threats echo the global cartel tactics he saw firsthand.

In the 1980s and ’90s, Colombia’s cocaine cartels controlled entire regions through intimidation, corruption and fear tactics that are nearly identical to what’s now unfolding in parts of Mexico.

“Their strategy is simple: if they can control the levers of power in a nation through intimidation, then they control the nation,” Peters said. “They assassinate police, judges and journalists, and they use fear to rule, the same way authoritarian regimes do.”

The difference today, he warned, is proximity. This time, the violence and instability are unfolding just beyond America’s southern border, in places millions of U.S. citizens visit each year for vacations and business.

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That closeness, Peters said, makes Americans prime targets for extortion, kidnapping and terror.

“My advice is simple: don’t go unless you really need to,” he said. “Be cautious, and stick to places with an established record of safety.”