A man livestreamed the Boulder grocery-store shooting and posted the footage - including shots of motionless bodies - on YouTube

• A man livestreamed the mass shooting in Boulder, Colorado, on Monday on YouTube.
• The video shows two motionless bodies on the ground outside the store and another inside the store.
• An expert said he would "absolutely not" recommend that a civilian enter and livestream a shooting.

A man livestreamed the mass shooting in Boulder, Colorado, on Monday afternoon, uploading the footage on YouTube.

The shooting at a King Soopers grocery store left 10 people dead, including one police officer. A suspect who was "significantly" injured was taken into custody, officials said.

The YouTube video shows three motionless bodies on the ground: one outside in the parking lot, one outside near the store's entrance, and one just inside the store. Within 10 hours, the nearly 3-1/2-hour video had more than 526,000 views.

In the video, the police and the state's SWAT team arrive, and officers later take a handcuffed man who appeared to be wearing only underwear and no shoes into custody.

The Colorado Springs Gazette identified the man who filmed the video as Dean Schiller, who identifies himself as a citizen journalist. The description of the YouTube video provided a link for media organizations to license the video for $87.97.

In the video, Schiller says he was loading groceries into his car when he heard gunshots. He says he then started a YouTube livestream on his phone and walked toward the entrance.

"I don't know what's going on," Schiller can be heard saying in the video as he approaches the entrance. "I'm at King Soopers in South Boulder. I heard gunshots. They were very close. Someone's down, right here."

Schiller films a motionless body lying on the concrete outside the entrance near a shopping-cart corral, and another body out in the parking lot. He asks someone who appears to be a King Soopers employee whether he saw which way the shooter went.

"He went in there," the employee says, pointing inside the store. Schiller walks in the store and films another body on the ground, saying, "Oh my God. Guys, we got people down inside King Soopers."

Two gunshots can be heard. Schiller exits the store and continues filming from the parking lot.

About 10 minutes into the video, Schiller says that his friend was inside the store and that the friend had just tried to call him but he couldn't answer.

Schiller did not immediately respond to Insider's request for comment for this story.

'It's very hard to understand the benefit of doing something like that'

Matthew Johnson, the director of training at Cohen Security, a California company that provides active-shooter trainings to civilians and first responders, told Insider that he had not watched the YouTube video but would "absolutely not" recommend that a civilian enter an active-shooter scene.

"If you're just a civilian and not an authorized first responder and you really want to help, the best thing you can do is observe and report to 911 from a safe distance," said Johnson, who served for six years in the Israel Defense Forces.

Bystanders should minimize the chance of interference with first responders and law enforcement, who are trained to respond to such events, he said.

In the YouTube video, police officers can repeatedly be heard asking Schiller to move back for his own safety. At one point, Schiller tells a police officer urging him to move to "f--- off."

The YouTube video may not even be helpful to the police, Johnson said.

"In general, there can be a great benefit for law enforcement after the fact for footage that was taken at the incident," Johnson said. But most supermarkets are equipped with many security cameras, making the chance that the livestreamed footage is helpful to the police in this case "pretty much slim to none," he said.

Johnson said he didn't think that livestreaming a mass shooting was appropriate under any circumstances.

"It's very hard to understand the benefit of doing something like that in the middle of a situation like this," he said.

The video was still available on YouTube 10 hours after it was posted

The video remained on YouTube at the time of this article's publication, 10 hours after it was livestreamed.

YouTube's policy says the site doesn't allow "violent, shocking" content that's intended to shock or disgust viewers or encourage violence. This includes footage that involves physical attacks or corpses.

Schiller's footage did appear to show corpses, but YouTube said it kept the video up for its news context.

"Following today's tragic shooting, bystander video of the incident was detected by our teams," Elena Hernandez, a YouTube representative, told Insider. "While violent content intended to shock or disgust viewers is not allowed on YouTube, we do allow videos with enough news or documentary context. We applied an age restriction to the content and will continue to monitor the situation."

When considering removing content, YouTube also considers whether violent or gory imagery is the focus of the video, the amount of time violent imagery is seen, and whether the title or description of the video indicates an intent to shock or disgust viewers, the company says.