The U.S. attorney's office in Minnesota just wrapped up 21 more indictments of sex traffickers — part of its ongoing work to break up what have become sophisticated, international criminal organizations that exploit immigrant women and girls. To their credit, the exceptional work of prosecutors and investigators has not skipped a beat despite the loss of their former leader, Andrew Luger, who was forced to step down as U.S. attorney after President Trump requested mass resignations months ago.

Now a replacement must be named, and the question of whether and how that work will continue is a significant one. U.S. Sens. Amy Klobuchar and Al Franken of Minnesota are seeking a replacement to nominate, but one committed to carrying on the work already started. "Sex trafficking has become a horrendous problem in Minnesota and across the nation," Franken said recently. He said that he and Klobuchar consider it essential to nominate someone who will "continue this important work."

But this White House has a track record of appointing those with views contrary to the missions of offices they would operate. Minnesotans should make it a point to add their voices to those of their senators, making clear that the vital work this office has done to curb sex trafficking, both of juveniles and young immigrant women, along with its dedicated efforts on countering terrorist extremism, must proceed under a new U.S. attorney.

Acting U.S. Attorney Greg Brooker recently told the Star Tribune Editorial Board that he and his staff are pressing ahead with their work, building on the valuable, intelligence-sharing network forged with other law enforcement agencies and nonprofit organizations. They remain intent on wiping out what has become an organized crime network centered around the cross-country trafficking of modern-day sex slaves.

Sadly, Minnesota has become a hot spot for such exploitation. Brooker said traffickers are drawn by a combination of "tremendous demand here," and modern airports, roadways and shipping ports. The U.S. attorney, working with Homeland Security, the St. Paul Police Department and a host of others, has uncovered and now is prosecuting one of the largest sex-trafficking rings in the country. Their combined efforts have delivered what one agent called "a gut punch" that now is being followed up by Internal Revenue Service analysis to track the money trail across the world.

These are complicated cases, with webs that span nations and elaborate money-laundering operations that run into tens of millions of dollars. The work, Brooker said, is far from over. Traffickers have the sophistication and resources to create fictional identities for the women they prey upon. They evade U.S. immigration laws by fraudulently obtaining visas. Victims smuggled in then spend years working off the expenses incurred by their traffickers.

And now a marquee event is coming. The Super Bowl has become an unwilling magnet for sex traffickers and soon will land in Minneapolis. That will require a ramping up of investigative work, not a pullback.

A new U.S. attorney will, of course, have his or her own objectives for the office. But the efforts to curb international sex trafficking here and across the country have proved their worth: attacking harmful criminal activity, revealing weaknesses in the immigration system and halting the violation of basic human rights. That work must go on.