I really and truly wouldn't lie or try and cover anything up. You are right, children need to be protected but not from the truth. Children always need to know the truth.
Fear in children is often borne out of a lack of knowledge or understanding and out of feelings of not being in control.
By retelling the story in what, to you, is a less scary way you run the risk of a conflict of information which will mean your children lose faith in you, they wonder whether they can trust you and, ultimately they lose confidence in your ability to protect them.
Tell them the facts as you know them. Tell them the parts you do not know or understand, express your disbelief, your sadness your concerns and together formulate plans to help keep one another and yourselves safe. These plans should be general and not directly related to what has happened.
If you do all this you remain in control of your lives, the children see you coping with disaster and gain strength and courage from this. Most importantly they will see their parents as people that are honest and reliable and dependable and this will give them the ability to feel safe in the knowledge that there are at least one (or two) people in this scary world they can trust and rely on.