NOGALES, Arizona—The crowd was small, and Attorney General Jeff Sessions’s speech was short. But his message couldn’t have been clearer:

“This is a new era,” said Sessions, who sported a dark suit in the hot Arizona sun. “This is the Trump era.”

And with that Sessions officially weaponized the Justice Department to crack down on undocumented immigration. After taking a private border tour with Customs and Border Protections agents in Nogales, on the southern edge of Arizona, the attorney general announced the feds will soon be spending a lot more time prosecuting people who break immigration laws.

Sessions made the announcement over a glitchy sound system to a group of reporters and Customs and Border Protection agents just a few feet away from the Mexico border. A gust of wind knocked over the American flag behind him as he spoke, so a CBP agent stood behind it and propped it up until the attorney general finished his speech.

All federal prosecutors, Sessions said in his slow Alabama drawl, must now consider bringing cases against people suspected of the “transportation or harboring of aliens.” Those prosecutors must also look to bring more felony prosecutions against some immigrants who illegally enter the country more than once and should charge immigrants with document fraud—which includes using a made-up Social Security number—and aggravated identity theft when they can.

One veteran federal prosecutor told The Daily Beast these changes are a generating significant concern.

“It’s fucking horrifying,” the prosecutor said. “It’s totally horrifying and we’re all terrified about it, and we don’t know what to do.

“The things they want us to do are so horrifying—they want to do harboring cases of three or more people,” the prosecutor continued. “So if you’re illegal and you bring your family over, then you’re harboring your kid and your wife, and you can go to jail.”

Sessions broke the news on his first trip to the border as attorney general. The last time he visited was a few days before the 2016 presidential election, when he appeared with former Arizona Gov. Jan Brewer to talk up Trump’s tough-on-immigration credentials. During his time in the Senate, Sessions was a relentless advocate for much tougher enforcement of immigration laws. Now that he’s the nation’s top law enforcement official, he’s making good on those commitments—which this trip is highlighting.

Immigration-related crimes are already a massive portion of federal prosecutors’ caseloads; Syracuse University’s Transactional Records Clearinghouse found that immigration violations—including illegal entry and illegal re-entry—made up 52 percent of federal prosecutions from September 2015 to September 2016. In the Trump era, though, immigration offenses will be an even larger part of prosecutors’ work. It’s a move that delights immigration hawks.

“All of these steps from detention to more judges to prosecuting those who have previously been deported will drive down the number of illegals in the country and lead to even bigger drops in those trying to sneak across the border,” said Hans von Spakovsky of the conservative Heritage Foundation. “All of this is long overdue.”

The Federation for American Immigration Reform, a restrictionist group whose leaders have worked closely with Sessions on immigration issues and that has significant clout among Trump’s nationalist-populist allies and aides, takes a broad view of what kind of activity could constitute “harboring.” In a position paper on its site, FAIR says anyone who knowingly helps an undocumented immigrant get a job could be prosecuted.

Some view the change as a waste.

“Every dollar spent on prosecuting an illegal immigrant for illegal reentry is a dollar that could have been spent on prosecuting or investigating a real crime,” said Alex Nowrasteh, an immigration expert at the libertarian-leaning Cato Institute. “It’s a shame the government is prioritizing the enforcement of, essentially, labor market regulations over violent and property crimes.”

Others welcome it. John Huber, the U.S. attorney for Utah, told The Daily Beast his office has already been doing much of what Sessions called for—especially prosecutions related to people entering the U.S. illegally after previously being deported—but that he expects to bring more harboring prosecutions to comply with the guidance. That would include people who drive vans full of undocumented immigrants across the border and into Utah looking for work, he said.

“That’s the type of case we may see here, where you have someone transporting a vehicle full of unlawful immigrants,” he said. “We will go after the people who are transporting them, organizing, and coordinating that trip, bringing aliens into our country.”

Sessions made clear that the new crackdown won’t exempt parents of U.S. citizens.

“Will there be any mercy or latitude in prosecuting people who have U.S.-born children who are minors here?” one reporter asked.

Sessions didn’t blink.

“We want everybody to comply with the law,” he said. “And because a child or a family member enters the United States lawfully doesn’t mean that others can enter the country unlawfully. So we do have that challenge. We want people to understand that they’re not entitled to enter unlawfully. We want people to know that laws will be followed, and hopefully if we send this message—it’s already seeming to have an impact—we’ll be able to return to the kind of system we can be proud of.”

This new announcement is part of broader changes Sessions is making at the Justice Department which will lead to more deportations. And it comes at a time when many members of Trump’s orbit are getting flak from his diehard supporters for allegedly going soft on core campaign issues. Trump drew considerable criticism for the airstrikes on Syria, given that he campaigned against U.S. involvement in Middle East conflicts. And the defeats both his travel bans have faced in court are a glaring—if reversible—reminder that the president doesn’t always gets what he wants. But at Justice, Sessions has proved to be an unflinching, uncompromising enforcer of the president’s law and order agenda. And he’s just getting started.

—with additional reporting by Harry Siegel