Transcript for A Missing American and a Missing Drone
This week -- Brian Ross investigates. Missing in Iraq. Former FBI agent who disappeared in Iran and four and a half years ago appears on a -- dignity. The first sign that he is still alive. Also missing in Iran US by. -- showed offered camp. Our expert mr. -- -- that inside look what's going on inside that Americans and Brian Ross investigates. Here now -- ABC news chief investigative correspondent Brian -- For years the US has treated the abduction a former FBI agent Bob Levinson from an -- resort four years ago as a diplomatic issue. Rather than international hostage standoff. The emergence of a proof of life hostage video. Taken last year and released by his family last week has deepened the mystery surrounding the -- kidnapping. And further complicated an already tense US relationship with a -- Beautiful -- -- wife Christine. American officials thought Levinson was dead until this proof of life hostage video was sent to his wife in an anonymous email. -- posted today on his family's web site. -- certainly help. I'm okay. Quickly I'm -- he's. He has probably lost about 75 pounds. And the shirt he was wearing is actually the shirt. He wore when he does. -- a former FBI agent was working as a private investigator. When he disappeared in 2007. On the Iranian resort island of kitsch where Americans can go without a visa. And it remains a mystery Estes who in Iran kidnapped -- or -- On the video recorded at least a year ago Levinson purposely avoids naming his captors in his plea for help. Current review news service. The United States. There's something. The -- family says it posted the video and its own statement with mrs. Levinson wearing a head scarf and her son David next in an effort to start negotiations. With whoever has. Please help us. We tried to contact you but you never responded. Levinson has seven children and two grandchildren one he has never -- and the holidays the family says are especially hard. The frustration is that every day passes and he's still not home with us and I don't know how to get him. Iran has denied holding Levinson. But US officials believe someone or some faction and that country is responsible and control of the americans' -- But the recent tensions with -- -- Including the -- drone that they found from the US have made it increasingly difficult for FBI negotiators. To make any progress in the efforts to free their former -- Joining us now to discuss Lebanon's abduction is Richard Clarke former White House -- terrorism advisor and Allen ABC news consultant. And did I do Bob Levenson have known him for thirty years to see that video is quite wrenching. I think -- everything he says there he's been told us. Well you can be sure of that prior and he's been given a script and he's been told to read it. If he did anything else they wouldn't have released it. But you know this is a real who done it because. It's not clear who hasn't. Al-Qaeda doesn't appear to be a player here -- MO is that they announce. When they have a hostage. He doesn't appear to be the Iranian government. In a formal sense. Because there -- style. Is to arrest people. And then to announce that they have been arrested in the put them on trial. Part of the answer might be where he was last seen. As you said it was out and uranium resort. But not in mainland Iran -- was on the island called Kish. Which is a bit of an international zone you don't need of these -- go there -- an American. And it's also a place where a lot of smuggling takes place. It's conceivable. He ran afoul of some group that was perhaps criminal gang. We've. -- ties in to local police or local government security services. Some sort of arrangement of convenience between the criminals and the local authorities. And by being there and perhaps disrupting that. He was seen as their enemy and in fact he was investigating. Cigarette smuggling -- the tape was sent to Bob -- wife via email. They tracked back -- it came from. It appeared to be server that was up for a day or two. In Pakistan and Afghanistan and then disappeared it appears whoever sent it was making it seem that the tape came anywhere but Iraq. Perhaps pointing a finger. Well that's right and as you know Brian it's extremely easy. To spoof the Internet address the IP address. Of -- server. It's also very easy to models through multiple countries -- multiple servers so. What we see in that last email IP address coming to his wife. Doesn't really tell us very much about where it originated. The US says he was not in any way working for the US any agency of the United States government when he went to to that island. And it's been a dilemma for the US if they push too hard. There you fear it may look like they're trying to defend their agent when in fact he's not. What's your best thoughts on the right approach to this four and a half years -- since he disappeared. Well I think the United States government can only do so much. He's not -- US government employee anymore we don't have an embassy in Tehran which obviously don't very good diplomatic relations. -- -- -- When the two or three originally Americans so called hikers. Were arrested on the border. With Iraq. The United States tried through various diplomatic channels. But ultimately it was another country it was the Sultanate of Oman. That stepped in and was helpful. And that -- being the route or similar route. To talk to the Iranian authorities. And also the authorities and Afghanistan because he could be there. And see if something can be worked out. Eleventh and tape came out at the same time that Iran announced it has brought down -- US spy drone that flew over me territory. The US denies adamantly that Iran brought it down it came down on its own USA. What's your thought how to that end up in Armenian hands and so embarrassed the US. Right here's a case where I'm not buying what the US government is selling on this I'm not at all sure. That the US government knows enough. To say that the Iranian government didn't steal it didn't take control of it. What we know. We know a couple of months ago. The drone headquarters in Las Vegas. Had the virus from the Internet running on its computers. A so called keystroke logger that was recording all the commands being given to the drones. That -- run them out of the Las Vegas headquarters. So that means that you can't hack your way in to the controls somebody -- in if this system were really airtight. If you were really separated from the Internet. That wouldn't be possible. That we brought though they brought Italy down. And encampments and I think they could have. I think they could have you know that of these drones use a commercial satellite they're up linked to a commercial satellite. And we also know that the Iranians recently. Acquired from Russia very sophisticated electronic jamming capability. That was designed to do things like take control. -- over frequencies like this so I'm not ruling it out. And I think Nolan in the US government should be ruling out the possibility. That Iran took control of the uplink. Then flew this thing into Iran and landed it because it certainly looks. Like it's in one piece and on damaged. And finally Dick how big -- -- -- this for the US this is obviously very advanced technology. In the hands now -- banana. Well it is a big loss. But not it's not every thing we know about how to make these vehicles. Can be learned by looking up more. The manufacturing techniques and technology. Are really what's key to this and that won't be too obvious just by having one in in their possession but -- in the larger picture here is. There appears to be a Covert war. Going on between the United States and direct. To. Our thanks very much that's all the time we have for today for updates on this story and other breaking daily investigations. As an abcnews.com. Slash blotter. You can also follow me and the ABC news investigative team on FaceBook and Twitter. Thanks for watching we'll see you here next week.
This transcript has been automatically generated and may not be 100% accurate.