Major news and reputable sources will almost 100% of the time copyright their images.  For example, the Featured image of this post by National Geographic, has complete meta data.  Meta data is the data about the data and in the case of images, the information about who, what, when, and where the image was taken.  With respective rights to the photographer who took the shot.  This is only fair to protect our creatives in the industry.

Other Features:

• Sharpness and blur – the image above has tell tail signs of fake as the sharpness and blur is inconsistent and looks artificial.
• Using images.google.com for a revers image search can tell the story of a fake image
• Try to find the image on a real reputable news source.