Republican U.S. House Speaker Mike Johnson made a pit stop in Minneapolis on Sunday to campaign with House GOP candidate Joe Teirab and preview the party's line of attack against Gov. Tim Walz in his home state.

Standing outside what's left of the old Third Precinct police headquarters that rioters burned after the police killing of George Floyd, Johnson, Teirab and U.S. Reps. Pete Stauber and Michelle Fischbach warned that the precinct stands as a symbol of what's to come if Vice President Kamala Harris and Walz are elected in November.

"Right here, the hopes and dreams of countless small business owners and families literally went up in smoke," Johnson said. "And as you can see from the charred and barricaded building right behind us here, four years later, this community still has not recovered from the aftermath."

The Republicans blamed Walz for letting Minneapolis burn during the riots and they took aim at Harris for supporting the Minnesota Freedom Fund (MFF), a nonprofit that pays for bail and immigration bonds for those who can't afford to do so themselves.

MFF was flooded with donations during the riots and helped bail out protesters. Harris also helped drive donations to the funds by posting about it on social media.

"While Tim Walz let Minnesota burn, it was Kamala Harris who poured gasoline on the flames by helping to bail out those who held the matches," Johnson said. "Five days after the riots began, and there were millions of dollars in destruction, Kamala Harris helped raise money, not for the people whose businesses were being destroyed, or the lives that were ruined, but for the criminals who destroyed them."

Just over a year into Walz's first term as governor, Floyd was murdered by then-Minneapolis police officer Derek Chauvin. Video footage of the killing ignited five days of protests that escalated into riots, causing roughly $500 million in damages across the Twin Cities, including the May 28 burning of the third precinct.

Since the riots, there's been widespread debate over whether the National Guard should have been sent in earlier to quell the unrest. And there's been blame over who was at fault for allowing the riots to spin out of control, though Minneapolis- and state-commissioned reports cited a breakdown in communication.

"The riots in Minnesota show what a Harris-Walz administration would do," Fischbach said. "They will let law enforcement down. … They will let the people of our country down."

The Harris-Walz campaign shot back at GOP characterization of the riots, arguing that Walz "took action" while former President Donald Trump did not.

"Trump's only contribution that week was sending tweets from his bunker saying the military should shoot protesters. There's only one candidate for president who is responsible for starting a riot, and that was Donald Trump on January 6th," Walz campaign spokesperson Teddy Tschann said.

Johnson's visit came nearly two weeks after Teirab won the Republican primary to take on Rep. Angie Craig in one of the most closely watched House races this cycle that could determine control of the body.

Johnson would not say where he thought the Second Congressional district ranked in Republicans' projections of winnable House races, but his visit to Minnesota highlighted the importance of the seat to national Republicans.

The House speaker predicted that Teirab, who beat conservative grassroots candidate Tayler Rahm in the primary and has been backed by Washington Republicans, would beat Craig "handily."

"The projections for the outcome of the House races are favoring Republicans right now," Johnson said. "We believe that we are going to grow the majority, and part of our belief is based upon the fact that we have extraordinary candidates like Joe Teirab."

Craig's campaign manager Rachel Rothman hit back criticizing Teirab's position on abortion.

"Voters in CD2 value their freedom far too much to elect lifelong anti-abortion activist Joe Teirab, no matter how much money establishment Republicans raise for him from out-of-district donors," Rothman said. "Hope Joe got to show the Speaker around his neighborhood in Minnetonka while he was in town!"

Teirab opposes abortion but with exceptions of rape, incest and saving the life of the mother. He opposes a federal abortion ban and believes it's a state issue.

In recent weeks, Rep. James Comer, the Republican head of the House Oversight Committee, launched a probe into Gov. Walz's longtime ties to China, as his past working with the country that has had a shaky relationship with the U.S. has come into focus now that he's Harris' vice president pick.

Walz moved there to teach English in 1989 as one of the country's first U.S.-sanctioned educators and has since visited the country more than 30 times. He also used his experience as an educator in China to influence U.S.-China policy during his six terms in Congress, often as a critic of the country's human rights abuses.

Johnson said he thinks the Oversight Committee's investigation is "an appropriate thing for them to be looking into."

"The House Oversight Committee has pretty broad jurisdiction and one of the things that they're tasked with doing is safeguarding the American people, looking into things that are questionable," he said. "In regard to China, that's our closest peer-to-peer adversary right now. China is our greatest national security threat, next to the national debt. We have to take it very seriously and the allegations that have been made against Tim Walz are quite serious."

Minneapolis crime and policing reporter Andy Mannix contributed to this report.