Attacked

Every city on Earth with a population of fifty thousand or more is attacked by aliens who exterminate the political, industrial, economic, and military leadership of the world. Over seven billion people are disintegrated in two hours. Eleven people discover the general area where the alien command post on Earth is, and set out to attack it. They don't know its location, have no plan of attack, and don't know how to get into the command post if they do locate it. And not all of them are convinced they will succeed. But two people join them who know something about the aliens. They have nine days to travel a thousand miles without being seen, and get into the command post and stop a fleet of one hundred alien ships from reaching Earth and completing their conquest of Earth. And the aliens are prepared for them.