"It maybe as simple as adjusting the light but it's only done to sensationalize the scene and not to show the true scene."
Obviously I don't know how many have been seriously altered, but every photographer in the world manipulates light, focus, composition etc either while taking the picture or after. That's what makes a good photographer. Anybody can point and shoot.
News photographs, however, should not be altered in a manner that changes the story in the least bit. It's one thing to get the best lighting. It's another to add elements to the picture that were never there.
I have a fairly good digital camera and whatever I download is what I get. My point isn't what makes a good photographer because these people are supposed to be professionals which makes it more unreasonable why they would use software to adjust (distort) their photos unless all they're trying to do is sensationalize the scene.