the Daily Mail has come up on more than one occasion for running stories that turn out to be largely fabrications and that mainstream news sources such as the BBC and The Guardian have not run. you'd think that the nature of the story (ISIS accidentally blowing up its own fighters) would get very wide coverage - but it hasn't [emphasis mine] - this is because the BBC and Guardian have their own biases, particularly The Guardian.
The Guardian doesn't run half the ISIS news that appears in The Mail because The Guardian would ideally like to sweep the Islamic terrorist problem under the carpet.
I found the following in today's Mail but not in The Guardian (likely because it goes against the 'Muslims are peaceful' crap).
It's about an Iraqi who apparently lost 4 elder brothers to ISIS. This remaining brother has allegedly fought and killed 130 ISIS soldiers in battle, and he's allegedly beheaded 50 captive ISIS prisoners, a la Jihadi John.
Warning: article contains images some may find disturbing ...