already confiscated those crucial black boxes, vowing to send them to russia, former ntsb director tom houderls us, the data inside them cannot be altered without detection. >> it's very easy to tell if somebody has tampered with that data. so i'm not overly concerned about that. the key now is to get that data to the authorities as quickly as possible. get the specialists on hand and download the information. >> perhaps of more concern is the integrity of the crash site itself. in a war zone, maintaining a crime scene is not always the first priority. >> that's a major concern. any time you have an uncontrolled accident site, parts vanish. it's just the way it is. we don't want that to happen here. obviously, if they start removing parts, they may remove parts that are critical to the investigation. they don't know what they have. so there needs to be some control over the site. any part that walks off, if you will, may be the critical part to help understands what happened here. >> a ten-mile debris path, with clues, answers, and the victims that carry them, now all guarded by hostiles, per