What's the Difference?

What is the difference between wounded and injured? I hear these words used interchangeably on NPR reports that drift into my office on radio waves.

When someone is writing a news story, how do they decide which one to use? What does one convey that the other doesn't? So, I started thinking about it. I scanned my brain for an answer. Here's what I came up with:

To me, to be wounded means someone/something has inflicted bodily harm upon someone else, i.e. "The wedding party was wounded when a suicide bomber detonated himself outside a temple in Tel Aviv." Whereas injured carries for me a tone of accidental injury , i.e. "A woman was injured when she dropped a bowling ball on her foot."

Now, I don't claim to have a firm grasp on the English language, I almost used cadre incorrectly in a sentence yesterday, so I consulted several references and here's what they had to say:

To injure implies the inflicting of anything detrimental to one's looks, comfort, health, or success, where as to wound implies an act that causes bodily injury, especially the puncturing of one's skin.

Hmmm...the difference is still not clear to me. I suppose I'll need to pay closer attention to how others are using them.