By the time Christopher Key and his half-dozen followers reached the Springfield, Mo., Walmart pharmacy counter on Monday evening, the metal shutters were nearly fully drawn.

An Alabama-based anti-vaxxer who has gained a following online — where he spreads false information about the coronavirus pandemic, Key was on a mission to give the pharmacists inoculating shoppers a warning.

“What they’re doing is crimes against humanity,” he said in a live stream on Facebook. “And if they do not stand down immediately, then they could be executed. They can be hung in the state.”

Key, who did not immediately respond to The Washington Post’s request for comment early Thursday, was invited to Springfield for an anti-vaccine rally this past Saturday, according to the Springfield News-Leader, which first reported the Walmart incident. Videos on Key’s Facebook page show he also spoke at a Springfield Public Schools board meeting and made the rounds to other pharmacies, where he bombarded workers with similar false rhetoric.

The stunts in Missouri come as the state remains a covid hot spot. Its death rate is among the worst in the country.

About 51 percent of Missourians are fully vaccinated, The Post’s vaccine tracker shows, which matches the national rate. Last month, Missouri joined a handful of other states seeing a notable uptick in vaccinations as the highly contagious delta variant continues to ravage communities, The Post reported. But many residents — specifically in Springfield — are still wary of the vaccine.

Key has a history of making discredited medical claims. A 2013 Sports Illustrated feature chronicled his sports supplements business, which sold deer antler spray to several high-profile athletes as a remedy for injuries and “concussion caps,” which were essentially beanies, to pro football leagues.

The Alabama native has become a popular figure among far-right online communities. He dubs himself the “Vaccine Police” and posts several live streams on his Facebook daily, many of them featuring false information about the pandemic as he drives city to city to rail against the vaccine.

On Monday, about a half-dozen supporters joined Key outside Walmart. One woman said she drove three hours to be there for the confrontation.

“Any opportunity to take down Western medicine and Big Pharma, I’m all over it,” she can be heard saying in the live stream.

Wearing a polo with “Vaccine Police” written across the left side of his chest, Key ran through the game plan with the group. During a prayer in the parking lot, Key said he hoped to “put the fear of God in these pharmacists.”

The live stream shows Key walking past the produce section and then along the grocery aisles. As he made his way to the pharmacy counter, workers there can be seen shutting down the counter and locking the door.

“Wow! They’re going to close down the pharmacy,” Key said.

A representative for Walmart told The Post the company had no comment.

Key went on to claim that the pharmacists were violating the Nuremberg Code, a set of medical ethics rules established after World War II that led to the prosecution and execution of several Nazi doctors who carried out medical experiments on victims in concentration camps. Key’s comparisons are inaccurate, experts say, because the coronavirus vaccine is not experimental.

“If you allow one more shot in one more person’s body, you yourself will be executed in violation of the Nuremberg Code,” he said as he pointed to a Walmart employee standing nearby. “We don’t want that to happen to any of you guys at all. We love you guys. We want to keep you safe.”

Key repeated false information about the vaccine, saying that it is “experimental” and referencing an affidavit from America’s Frontline Doctors — a group known for spreading misinformation about covid — that alleges some 45,000 people died days after getting the shot. (There is no evidence that the claims in the document are accurate.)

About 10 minutes after confronting the Walmart employee, who mostly remained silent, Key switched his tune. He was actually there to get the vaccine, he said.

“Why can’t I get my vaccine? I’m here to get my vaccine,” he said.

After about 20 minutes loitering outside the pharmacy, Key and his posse left the store and encountered a police officer waiting outside.

“She just refused me my vaccine,” he said to the officer, referring to the female employee. “What if I die tonight and I get covid because I didn’t get my vaccine?”

Three more police officers arrived before Key decided it was time to leave.

“You don’t intimidate us,” he said.

Later that day, Key went to a Walgreens and CVS, his Facebook shows. On Tuesday, he filmed himself ambushing Steve Edwards, the chief executive of the hospital system CoxHealth, in a parking lot.

In a live stream on Wednesday, as Key drove out of Missouri, he falsely warned his viewers that the reports of fully occupied beds in intensive care units in Alabama hospitals were a lie.

“If you’ve got the common cold … they are putting people in comas and putting [them on] ventilators,” he said.

He also claimed the state was “trying to blame” the surge on people who are unvaccinated.

“We know the only people that are getting sick for the most part are those that are vaccinated,” he said.

The Centers of Disease Control and Prevention says otherwise, reporting that vaccinated patients make up a small percentage of hospitalizations.