Soon after a tanker truck drove into a crowd of protesters on the Interstate 35W Bridge in Minneapolis, Minnesota House Majority Leader Ryan Winkler sent an alert to his thousands of Twitter followers.

"Protesters I know are saying truck driver drove into a crowd and intentionally ran into them," the Golden Valley Democrat wrote Sunday. "Confederate flags and white supremacist insignia."

The tweet spread quickly, racking up hundreds of shares. But it wasn't true. Confirmation of Confederate flags or symbols never surfaced. State officials now say they believe the driver was already on the road as it was being closed and was not trying to hit anyone. No charges have been filed.

Through the chaos of a riotous string of days following George Floyd's death under the knee of a Minneapolis police officer, Winkler was hardly the only public official to unwittingly disseminate false or unverified information about the facts on the ground.

St. Paul Mayor Melvin Carter apologized Saturday for saying "every single person we arrested last night" was from out of state, after data showed most were from Minnesota. The mayor said he received inaccurate figures before the briefing and has "taken further steps to safeguard our ability to provide relevant and accurate information."

Even Gov. Tim Walz, who criticized Winkler's now-deleted tweet as "not helpful," had to walk back some statements he gave as he led the state's response.

On Saturday morning, as the Twin Cities reeled from another night of unrest, the governor blamed outside agitators for the worst damage to Minneapolis and St. Paul. About 80% of protesters, he said, were from out of state. President Donald Trump amplified the claim in a tweet to his 81 million followers.

When pressed later on the source of his figure, the governor cited "reports from what we're getting on the streets" and "human intel." By Monday, Walz had backpedaled, saying he "got out over my skis a little bit" by sharing an exact number. While some arrests have involved alleged rioters from out of state, officials have not confirmed publicly who was responsible for the bulk of the damage. Investigations are ongoing.

Rumors and false claims about the aftermath of Floyd's death surged over the past week, fueled largely by social media. Media research company Zignal Labs has tracked more than 1.7 million mentions of misinformation related to Floyd's death on May 25 and subsequent protests. Some top state officials have expressed concerns that some disinformation is being deliberately spread.

But public officials are not immune. In Minnesota, unconfirmed reports about drug cartels and white supremacists, a National Guard retreat and plans to block cellphone service during protests flourished after coming up through official channels.

The swirl of rumors during the Twin Cities' nights of arson and looting illustrated how relaying accurate information is crucial for ensuring public trust and safety, especially in times of crisis. The spread of misinformation, even when unintentional, can sow confusion and division.

For those reasons, public officials face "a higher bar" for getting things right, especially on social media, said retired Carleton College political scientist Steven Schier. But meeting that standard can be particularly challenging amid a "fog of conflict," he said.

"They're trying to make real-time assessments," he said. "A lot of that information is going to be fuzzy or false and they have to correct it as they occur."

Charlie Weaver, a former chief of staff to Gov. Tim Pawlenty who served as Minnesota Department of Public Safety commissioner during the 9/11 attacks, said he learned in those roles "to be honest and transparent about what we did know and what we didn't and when we made a mistake to acknowledge that and correct it as soon as possible."

"Mistakes are inevitable in chaotic situations," said Weaver, who now leads the Minnesota Business Partnership. "It's how you respond to them that matters and preserves your credibility."

In most cases, state and local officials did seek to quickly update or correct incomplete or inaccurate statements related to the unrest. A top Walz aide noted that the governor and public safety officials held multiple news conferences over the weekend in an attempt to provide updates as quickly as possible.

Winkler said he, too, was trying to share information of public interest in real time when he sent his tweet about the tanker truck. After the truck incident, he encountered a crowd of panicked protesters running his way. Someone he knew told him they had seen flags and symbols on the truck. The claim seemed "plausible" given top officials' earlier warnings about threats from white supremacists, so he shared the information, noting it came from a protester.

But when the DFL leader watched video footage of the incident later and "didn't see anything like that at all," he deleted his original tweet.In a follow-up post, he said he had shared inaccurate information amid a "chaotic scene and multiple reports."

"The eyewitness account seemed to square with outside facts," Winkler said in an interview. "What I have learned is people who are conditioned to see or believe a certain thing in a panicked moment can see it, even if it's not there."

Emily Vraga, an associate professor at the University of Minnesota's Hubbard School of Journalism, said the sheer volume of misinformation in breaking news situations means "no one is immune" from inadvertently sharing false claims. But she said it "is incumbent on people who have a prominent platform to be especially careful."

"There is a special emphasis for people who do have that power, whose voice will not just be heard but have a lot of credibility, that they have to get it right to the extent they can from the get-go," she said.

Vraga recommends public-facing figures delete and correct inaccurate posts if possible to try to prevent the bad information from spreading further. But even when they act fast, it can be difficult to rein in a false claim online.

On Friday, as fires and violence ravaged parts of south Minneapolis, Council Member Alondra Cano tweeted that Walz "pulled out the national guard he had promised," leaving a gas station to burn. A Walz spokesman swiftly refuted the claim. But Cano's tweet, which remains online, was shared by hundreds of people online. In a separate post an hour later, she said she had confirmed "guard members are still in Minneapolis," just rerouted to other parts of the city. That clarification was retweeted just 32 times.

In an e-mail, Cano said she was focused on efforts to raise money to rebuild Lake Street and did not have time to discuss her tweets.

Torey Van Oot • 651-925-5049