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Over 20,000 people turned out to see former President Donald Trump at his "Save America" rally in Cullman, Alabama on Saturday, Aug. 21.

But the massive crowd turned on Trump when he encouraged them to take the experimental mRNA vaccine days after Cullman declared a Covid-19 emergency.

They cheered when Trump suggested it was okay not to take the vaccine.

"You know what? I believe totally in your freedoms," the former President said. "You gotta do what you have to do."

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Then things took a nasty turn when Trump urged the maskless crowd to take the vaccine.

"But, I recommend take the vaccines. I did it. It's good! Take the vaccines," he said.

"Naw, that's okay. That's all right. You got your freedoms. But I happened to take the vaccine," he said as the crowd booed.

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The boos turned to laughter when Trump said "If it doesn't work, you'll be the first to know."

According to the Alabama Department of Public Health, only 32.5% of the state's population has been fully vaccinated.

Trump received the vaccine back in January despite being immune to Covid-19. Trump and his wife, Melania, contracted Covid-19 and he was briefly hospitalized.

Earlier in the evening, Rep. Mo Brooks (R-Ala.) was booed when he suggested Trump supporters should stop being "despondent" over Trump's election loss and move on to the next election.

"Look forward, look forward, look forward," he said.