If riots like the ones in the UK started in the US, what role would the media play?

Would the mainstream media sensationalize events to grab viewers, or would they downplay the story to prevent panic and spreading?

Setting aside the fact that riot police and the National Guard would be quickly activated and not to mention the probable formation of armed citizen militias, this question is only about the duties of the media in reporting.

If we saw civil uprising, how would (or how should) the major news outlets handle it?