Mars, Lidl, others withdraw YouTube ads placed next to those by predators targeting children

Mars, Lidl, Adidas and others have withdrawn all advertisements from YouTube after some were found next to clips used by predators to target children.

Investigations by the BBC and The Times revealed that tens of thousands of "predatory" accounts have been used to leave explicit comments on children's videos. The video-sharing site's reporting system has been blamed for letting the accounts persist.

YouTube said it was cleaning up the site on an urgent basis.

A Mars spokesman told the Guardian: "We are shocked and appalled to see that our adverts have appeared alongside such exploitative and inappropriate content."

It added it had immediately suspended advertising globally on YouTube and Google. It added that advertisements would not return until it was sure YouTube had put safeguards in place.

Meanwhile, Lidl, Deutsche Bank and Cadbury and many other big brands are also said to have suspended advertising campaigns while the video-sharing site acts.

A YouTube spokesman said, "There shouldn't be any ads running on this content and we are working urgently to fix this."

The investigations revealed that clips uploaded by young children on YouTube had been used to make sexually explicit requests and post obscene comments.

The attention of the BBC was drawn to the problem by volunteer members of YouTube's Trusted Flagger programme who alert the site to potential violations of its guidelines.

The development comes just two days after YouTube announced a campaign to prevent inappropriate content and comments on its kids programming.

New Jersey-based Mondelez said it was ''deeply concerned" and had suspended its advertising on YouTube, USA Today reported. ''We are actively working with Google and agency partners on an ongoing basis to ensure brand safety, but recognise there is more to be done by all parties,'' Mondelez added.

YouTube reiterated that it had recently toughened guidelines for kids programming and noted that in the past week it had disabled comments on "thousands of videos" that could be targeted by predators and shut down "hundreds of accounts" of users posting predatory comments.

''Content that endangers children is abhorrent and unacceptable to us," the Google-owned company said in statement. "There shouldn't be any ads running on this content and we are working urgently to fix this."