I just saw the first link.
They may think that the ethnicity of the criminals is not the point of the article, it's the violence of the crime.
When I could not see the article before, I tried to search for it in English. I couldn't find it, but I found a 14 year old Iraqi girl raped by an Iraqi policeman, another 14 year old girl raped by an Iraqi soldier in Iraq, and yet another 14 year old Iraqi girl raped and murdered by American soldiers in Iraq. So maybe the problem could be that men who rape girls just have a low opinion of girls in general, not only Swedish ones.