The key words are "This just in".
Have someone introduce you, since it is often it is the anchorperson who directs the viewers towards the "breaking news", and that is where you will be able to sort of break the ice with the viewers. Imitate the guys from the weather channel; they are usually right at the epicenter of the action. Hence, use a background showing smoke, or "Earthquake 2012", or something that illustrates the problem. Look scared, hold on to your microphone prop, and just describe what you see--particularly the people, children, and homes that have been affected. Start by saying "This just in" and just work your magic through.