Warning: This article features disturbing content and mentions of suicide.

Video promoting self-harm tips -- spliced between clips of a popular video game — has surfaced at least twice on YouTube and YouTube Kids since July, according to a pediatrician and mom who discovered the video.

The suicide instructions are sandwiched between clips from the popular Nintendo game Splatoon and delivered by a man speaking in front of what appears to be a green screen — an apparent effort to have him blend in with the rest of the animated video.

"Remember kids, sideways for attention, longways for results," the man says, miming cutting motions on his forearm. "End it."

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The man featured is YouTuber Filthy Frank, who has over 6.2 million subscribers and calls himself "the embodiment of everything a person should not be," although there is no evidence that Frank, whose real name is George Miller, was involved in creating the doctored video. He did not immediately respond to CBS News' request for comment.

When Free Hess found the video on YouTube last week, she posted it on her blog -- warning other parents to take control over what their kids may be watching.

"Looking at the comments, it had been up for a while, and people had even reported it eight months prior," Hess told CBS News on Friday.

Shortly after she published her blog post, YouTube took the video down, saying it violated the site's community guidelines, according to Hess.

Hess said she spotted another version of the same video on YouTube Kids in July last year. She said she and many other parents from Facebook groups came together to report it, and the video was eventually taken down after one parent directly contacted an employee at Google. Google has not responded to CBS News' inquiry about the steps that led to the video's removal.

Hess said after seeing higher rates of suicide in children in her own emergency room over the last few years, she made it her mission to bring awareness to disturbing and violent content being consumed by children on social media. She said she's reported hundreds of unsettling videos to YouTube, with some success. On Friday, she found and reported seven more disturbing videos on YouTube Kids, and said they were just the tip of the iceberg.

"I had to stop, but I could have kept going," Hess said. "Once you start looking into it, things get darker and weirder. I don't understand how it's not getting caught."

YouTube Kids is meant to be a kid-friendly version of YouTube site for children who are 8 years old and under, but trolls have founds ways around YouTube's algorithm and are posting potentially harmful videos.

"They're awful. Absolutely awful," Hess said about some of the content on the YouTube Kids app.

She said she logs onto the app posing as a child, rather than an adult, so that she can see exactly what kids around the world are seeing. The videos Hess has found contain mentions or visuals of self-harm, suicide, sexual exploitation, trafficking, domestic violence, sexual abuse and gun violence, including a simulated school shooting. She said many of the kids she treats in the ER list videos on YouTube as a method used to learn destructive behaviors and self-harm techniques.

A YouTube spokesperson told CBS News on Friday the site works hard "to ensure YouTube is not used to encourage dangerous behavior." The spokesperson also said YouTube has "strict policies" that prohibit videos that promote self-harm.

"We rely on both user flagging and smart detection technology to flag this content for our reviewers," the spokesperson said. "Every quarter we remove millions of videos and channels that violate our policies and we remove the majority of these videos before they have any views. We are always working to improve our systems and to remove violative content more quickly, which is why we report our progress in a quarterly report and give users a dashboard showing the status of videos they've flagged to us."

However, YouTube kids has a history of letting disturbing and violent videos slipping past its algorithms. In 2017, searching the word "gun" on the app surfaced a video on how to build a coil gun, Mashable reported. Other videos at the time featured Mickey Mouse in a pool of blood and Spider-Man urinating on Elsa, the princess from "Frozen," prompting backlash.

"The YouTube Kids team is made up of parents who care deeply about this, so it's extremely important for us to get this right, and we act quickly when videos are brought to our attention," a YouTube spokeswoman told CNET at the time. "We agree this content is unacceptable and are committed to making the app better every day."

Since the backlash in 2017, YouTube has outlined steps it is taking to improve safety on its Kids app. In November 2017, the company outlined a new set of guidelines, including "faster enforcement" of community guidelines and "blocking inappropriate comments." In April last year, YouTube announced three new parental control features to give parents the ability to curate what their child is seeing on the app. There are also a number of other ways for parents to make the app safer, but non of them are automatic.

This week, new cases of inappropriate content prompted high-profile responses, including from Disney and Nestle, which pulled advertising from YouTube after a blogger described "a wormhole into a soft-core pedophilia ring" on the site.

YouTube said Thursday it was taking aggressive action, banning more than 400 accounts and taking down dozens of videos.

Critics say its approach to safety across platforms just isn't working.

UPDATE: @YouTube @YTCreators left a comment and provided an update on what they’ve done to combat horrible people on the site in the last 48 hours. TLDR: Disabled comments on tens of millions of videos. Terminated over 400 channels. Reported illegal comments to law enforcement. pic.twitter.com/zFHFfkX9FD — Philip DeFranco (@PhillyD) February 21, 2019

Parents remain concerned about safety both on YouTube and YouTube Kids. "We should start by educating ourselves, educating our children, and speaking up when we see something that is dangerous for our children," Hess wrote on her blog. "We also need to fight to have the developers of social media platforms held responsible when they do not assure that age restrictions are followed and when they do not remove inappropriate and/or dangerous material when reported."