By Siobhan Courtney
Interactive reporter, BBC News
The BBC's Interactive reporter Siobhan Courtney talks about the investigation into the 'video attack'.
Video-sharing website YouTube has removed hundreds of pornographic videos which were uploaded in what is believed to be a planned attack.
The material was uploaded under names of famous teenage celebrities such as Hannah Montana and Jonas Brothers.
Many started with footage of children's videos before groups of adults performing graphic sex acts appeared on screen.
YouTube owner Google said it was aware and addressing the problem.
The BBC was made aware that scores of sexually explicit and inappropriate material was uploaded.
In one video titled Jonas Brother Live On Stage, a user posted a comment saying: "I'm 12 years old and what is this?"
This kind of raid showed how easy it is to upload porn to a website that millions of people browse on a daily basis
Under other uploaded videos, online users posted comments such as: "Take the tags off, you'll get us caught." Another said: "Your gonna kill us all!"
As the disturbing videos were being uploaded, many viewers added them to their favourites and rated them highly.
One user believed to have uploaded some of the pornographic material videos is Flonty, whose profile states that he is 21 and from Germany.
He told the BBC: "I did it because YouTube keeps deleting music. It was part of a 4Chan raid."
4Chan is a bulletin board focusing on Japanese manga and anime but some of its more extreme sections have been described on online messageboards as "sick" and "horrifying stuff".
"Anything and everything can, and usually does, happen here. We have our very own unique culture, and there is no group quite like us anywhere out there".
When asked if he was concerned that children can freely watch such inappropriate material on YouTube, Flonty replied: "Children will find inappropriate material around the internet anyway.
"This kind of raid showed how easy it is to upload porn to a website that millions of people browse on a daily basis".
Google spokesman Scott Rubin told BBC News: "We are aware of the slew of pornographic videos that were uploaded.
"We are addressing them as we would any video that violates our community guidelines.
"In addition, any account we discover that has been set up specifically to attack YouTube will be disabled."
YouTube delete music because they have to by law. Half the time you'll end up with a same copy of that same song elsewhere on YouTube anyway, and even then there are other sources for music. Children DON'T JUST find porn that easily. What about people at work who have a legitimate reason for using YouTube? How would one go about explaining porn to their boss? Tony Williams, Liverpool
YouTube is a privately owned site. Why do people feel entitled to use the site as they please? Do they help pay for bandwidth? Google ultimately has governance of what content should be on a site that they own. In most parts of the world, anyone is free to set up their own personal website with streaming content for their cause. Let's just see how many views is generated beyond their own interest group. Sophie, Toronto, Canada
A lot of comments here seem to excuse this behaviour because "kids need to learn how they get here". As if parents should take this mindlessness as an opportunity to educate their children on sex and procreation. RB, Florida
Flonty-you may have shown how easy it is to upload this material. It's also easy to hit people with a car, but that doesn't mean you do it. The anonymity of the internet helps cowards. Martin Holloway, London, UK
People who think this is "amusing" or "to be expected" simply don't get the point of this - yes, our little children may have the ABILITY to look up these pornographic images thanks to the Internet's wide selection, but these people simply took away the CHOICE that these kids would have to look up the aforementioned items. I mean, think of what would have happened if you were a pre-teen or younger, and you found this video of your favourite recording artists performing a song you enjoy, and suddenly it cuts to the image of a lot of men demeaning and performing degrading acts on a female who is paid to perform as though she is enjoying it. You think YOU could understand what's going on? Plain and simple, the service providers should be given the information of the people who did these and suspend if not ban these people from the internet. David, San Antonio, USA
Better stop taking your kids to the zoo then. How are you going to explain why the Big Elephant is trying to jump on the Little Elephants back, if you can't explain your own species procreation. Ben Heap, Keighley, West Yorkshire
Mark from South Shields - explain to your seven-year-old that some louts uploaded some naughty clips onto YouTube that are only for grown-ups to see. Or if you're feeling particularly adventurous, pat him on the back and say: "That's how you got here, son." Not so difficult.
I seriously doubt that kids are going to be traumatised by having witnessed adult humans in the act of mating, nor by any education from their parents they receive in light of such an event. Heather, Glasgow, Scotland
Welcome to the 21st century. I am hoping that within the next few years enough people will have been exposed to the full diversity of sexuality via the internet that we can finally have some intelligent public discourse that acknowledges its existence rather than perpetually trying to suppress such information.
All people, children included, should have access to such information and be allowed to make their own decisions and come to their own conclusions about it. Though the YouTube raid is rather childish, it will force some parents to acknowledge and explain things to their children that they would rather pretend don't exist. Jona Andersson, Sweden
The problem is that the hackers intentionally tagged the videos under misleading names. So it seems to me that their intent was to get children to look at pornographic materials. The issue is more than just porn on YouTube. I'm all for freedom of expression and allowing people to upload whatever they want, but I'm not for dishonesty. And in this overtly sexual world, it gets hard for parents to trust the internet even though its becoming close to impossible to live without it.
True, there's porn on millions of sites which children could easily have access to, but there is a significant difference between that and interest groups purposely tricking and delivering porn to children in a Hannah Montana package on YouTube . Tiya, Miami, Fl
I understand their motives. I'm sick and tired of clicking on videos on YouTube only to be told it's been removed due to copyright. These ridiculous copyright laws are completely ridiculous and I know there are many who agree. Isn't it better that we listen/watch things on YouTube rather than not at all?
Like I said, I understand the motive, but i think there could have been a more constructive way of getting the point across. Shaun, Glasgow, Scotland
What a bunch of utter losers, thinking that was a clever trick to raise awareness of 'issues'. Those videos could really seriously disturb some kids. Dan, United Kingdom
This type of thing is rampant on the internet, and should not be allowed. The only solution is stricter government controls on the content of the internet, and harsher punishments for those who violate those controls. Everyone involved in this hacking attack should receive no less than 25 years in prison, and should have to register as sex offenders. Richard C. Mongler, London, UK
Flonty says "Children will find inappropriate material around the internet anyway." The difference being is that those kids will activly be looking for porn, not having it forced into their faces by this sad little man. Christine, Derby - UK
"Moderate all the uploaded videos? Are you insane?" said Michael, he's right because latest reports from a few days ago indicate 20 hours of video are uploaded every second. The only solution is to charge users for uploading content, while watching remains free. Ian Mayman, UK
So if kids can't find porn on YouTube, where else could they find it? Oh, that's right - on one of a thousand other tube-like sites that specifically cater to those who like the adult entertainment. And most of these websites only require you to check a box confirming that you are of legal viewing age (a claim that they're not going to crosscheck anyway). If you're concerned about the purity of your kids, take away their computers. Bentley Winston, Madison, WI, United States
Welcome to the internet. Nelson Mills, Los Angeles USA
Moderate all the uploaded videos? Are you insane? Ask YouTube how many videos get up loaded a day... and then think again. Michael, Surrey, UK
I let my kids watch YouTube under supervision, so how would I explain to my seven-year-old when a porno flick appears instead of the Jonas Brothers? The question is here that YouTube can be seen as a 'trusted site' and when this trust is violated by a few hackers it spoils it for everyone else. Mark, South Shields
Sites should either be child friendly or not I think the concept of being a portal for the interests of both children and adults is unrealistic and impossible to monitor when images, audio, and video or concerned. James, Houston, US
It's bad that such material was uploaded to target children, but let's remember what YouTube is all about, allowing people to upload videos, and to share them with the rest of the world and to do it free of charge. Now this second characteristic I believe will make it close to impossible for YouTube to have trained people sit down and scan every video uploaded. If you are concerned about your kids watching such stuff, please take the pain to protect them. Saba Mahmud, HE, IL
For those who wanted to protest the loss of music from Google, it doesn't seem very inventive to upload porn to YouTube. If they really wanted to make a more distinguished protest, they could have plainly made a video of their own and uploaded it instead of acting cowardly as they have. Kelly , Crofton, BC, Canada
I think mass censorship and administration of YouTube is not a possible solution. It's the internet after all and things like this are bound to happen. I think too many things are being done to stop children from seeing things that they are bound to see one day or another. Mike, Wrexham
I am not overly worried about pornographic clips. What I am worried about is that no one is concerned about all the violence everywhere on the internet. And this violence is treated as the most normal thing in the world. I rather have kids watch porn than violence. Johannes, Netherlands
Children are exposed to scenes of horrible violence in the media every day, as well as advertising designed to affect them on a psychological level. This is acceptable. But show them any kind of pornographic image and suddenly they are victims. Derek, Taiwan
I think any material uploaded a website aimed at people of all ages should assessed by an administrator before being publicly displayed. Simple as that. Kirsty, Lichfield, UK
Pre-moderating uploaded videos is not a viable option for a site as huge as youtube. Any video that is inappropriate will be flagged by the community and removed. Videos can be removed faster than they can be created/uploaded, so they shouldn't really worry too much about it. John, Lancaster, UK
I find these attacks very disgraceful, as much as they want to protest against Google removing music, it does in no way warrant an attack using pornography. In fact I wouldn't say it was an protest against the music but a method to please the people uploading this filth. Carl Davidson, Carlisle, Cumbria
I am not surprised at what happened. I cannot turn a page in a magazine, watch a television program, listen to the radio or any other means of media where I am not assaulted by sexuality being the forefront to sell whatever it is the advertiser is wanting to sell and paying the media enough money to run it. Then we complain when society portrays just that. Marie, Canada
Not particularly surprised, and am partially amused, that this happened. Granted, I don't relish the idea of pre-teens being exposed to pornography, but it is a laugh. And for every parent who screams bloody murder at their precious little ones seeing that sort of material, a piece of advise - do as my father did, and a) monitor where your children go on the internet and b) have a relationship in which they'll respect you enough not to go looking for such things, and will turn away when they see it. Not nearly as difficult as one would think. Valentia, Baltimore, USA
Yes, there should be greater restrictions to upload a video on such sites. Otherwise, one can upload anything as we can see. Sajib, Dhaka, Bangladesh.
This could be a serious problem - not because of the idea that children could see this material but because it's a rare occurrence which could cause catastrophic results: censorship. And serious censorship at that - with people using this incident as an excuse to begin censoring video's not suitable for children. Youtube is a fantastic medium that self-censors amazingly well - what, I hope, people understand is that this is one situation and a minority out of the majority of users that post non-pornographic content and follow the rules. Nicholas Mills, Glasgow, Scotland
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