MARTINEZ, Calif. (KGO) -- A shouting match was caught on camera in a Martinez Walmart after a man questioned why a woman entered the store without wearing a face mask.
A man filmed the tense encounter with fellow shoppers on July 19, which he said was sparked after he asked one of them why she came into the store without a mask on.
On July 15, Walmart announced a policy requiring customers to wear masks while in-store. However, Walmart said the policy would not be enforced until July 20 to give it time to "inform customers and members of the changes, post signage and train associates on the new protocols."
In the video shot by Brian Campbell-Miller, he is in a queue behind a woman and her two children, none of whom are wearing a mask.
He told ABC7 News, "She's like, 'Well, I'm not sick,' and I said, 'Well, you know, you don't always show symptoms when you're sick.' And it's about being courteous."
FULL VIDEO: Dispute over wearing face masks in Martinez Walmart store goes viral
The woman is captured telling Campbell-Miller, "If it really mattered, the masks you're wearing... We would all be wearing the same mask, if it mattered! You can put me on Facebook I don't care."
ABC7 Special Correspondent Dr. Alok Patel weighed in, after watching the viral video.
"First of all, masks are a physical barrier. We know they work," Dr. Patel said.
"And different types of masks work differently, which is why you see people wearing cloth masks, you see people wearing home-stitched masks, and you see medical-grade masks. The physical barrier is what works," he told ABC7 News. "That's like saying, 'Hey, we all wear the exact same helmet.' No, there are different types of helmets."
The quickly-escalating situation gained the attention of two other women, who were also not wearing masks.
"Stay home if you're so scared," one said, moments before accusing Campbell-Miller of destroying "this country." Another calls him "Antifa" and aims the word "brainwash" at him.
Dr. Patel added, "It's the other way around. If you don't wear a mask, unfortunately, you should be the one staying home... Because you're at risk of getting people all around you sick. It's not necessarily the law, but it's a business's policy. So, maybe you should not be going to that business."
The first woman can be heard later telling another customer with children that the Centers for Disease Control and Prevention (CDC) has said that "children should not be wearing masks."
Patel chimed in, "The CDC actually says children under the age of two shouldn't be wearing a mask. In the video, those kids in the video are clearly above the age of two and they should be wearing a mask. That's another huge point we need to talk about when it comes to reopening schools. So no, the CDC doesn't say that."
"This video is only two minutes long and illustrated how far the misinformation rabbit hole can push people," he continued.
VIDEO: Dr. Patel's full fact check on viral video of Walmart mask dispute
The woman is also heard telling the man, "you're making yourself sick by wearing the mask."
"That is unequivocally not true," Dr. Patel told ABC7 News. "Wearing a mask is not going to make you more sick. And if you need proof, go talk to somebody like a surgeon who wears a mask for hours a day, for years. It's not going to make you sick."
As of July 21, the United States had the highest number of COVID-19-related deaths globally, with the John Hopkins University coronavirus tracker recording a total 140,909 fatalities.
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Campbell-Miller said he'll continue to speak up, especially when it's his health and safety at stake.
"I needed to do something about it, so that other people know that this isn't okay," he said. "And Walmart needs to step up and actually enforce their policies if they're going to have them."
Campbell-Miller admitted, "There were some employees, Walmart employees, that were trying to talk to her. But at no point did anyone say, you need to leave, let us escort you from the premises. And for sure, the security guard was not having it at all."
"It seemed like he had not gotten any training about what their store's policy was or how they were supposed to be enforcing it," he continued. "Because, according to her, he let her right in. He just told me to stop recording."
In a statement, Walmart told ABC7 News, ""It's unfortunate that a person would behave this way in our store. We appreciate our customers who take the health and safety of others seriously."
ABC7 News has followed up to ask about what responsibility the company had in this matter, and how it plans to uphold its own policies.
This story will be updated to reflect any response from Walmart.
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