Perhaps "covered up" is the wrong term, though failing to release information is pretty close.

Surely the sexual assault in Cologne matters. I'm not sure I understand your response to this. I'm informed that when the events in Cologne were not being reported, far right sources spread not entirely trustworthy information. All the more reason why it is important for trustworthy media sources to report on information when it happens to establish the truth, rather than censoring themselves about stories that are clearly in the public interest.