As the reporter in the following Sky News video helpfully explains, this proves that Gaddafi is not observing a ceasefire, paving the way for Western military action against Libya.
Here is another video of the plane:
But hang on.
Exactly when was this plane shot down?
Here is a video of a downed jet close to Bengazi that was posted two days ago on March 17, BEFORE the ceasefire was announced.