the secretary of defense, we do know here that at the heart of the hostage crisis is a shadowy figure, a renegade terrorist deploying new tactics. Abc's chief investigative correspondent brian ross is... See More
the secretary of defense, we do know here that at the heart of the hostage crisis is a shadowy figure, a renegade terrorist deploying new tactics. Abc's chief investigative correspondent brian ross is back on that part of the story tonight. Reporter: Almost overnight, 40-year-old mohktar belmokhtar has become one of the most wanted terrorists in the world, anytime americans are taken hostage, the man behind the hostage-taking becomes a well known house hold name. Reporter: The suspected mastermind of the algerian attack is believed to have run the operation from his safe haven, 1,000 miles away in the country of mali. And now, the u.S., England and france are setting their sights on the one-eyed belmokhtar and his rogue group of al qaeda fighters. They've been at this a long, long time. Reporter: One of his recent kidnap victims, robert fowler of canada, held for four months until freed in 2009, says he dealt directly with belmokhtar. He's very, very cold. Very business-like. Very focused. Reporter: And someone, fowler says, who clearly targets americans and other westerners. Brian, I cannot tell you the extent to which they hate us. They believe we are evil incarnate. They believe the west is one great sodom and gom morra. Reporter: Which is why the emergence has led to u.S. And french military action in unstable african countries that were never before seen as terrorism threats. When this incident is finally over, we know we face a continuing, ongoing problem. Reporter: The problem, the fear is that africa could turn into a new afghanistan, where al qaeda is establish training bases and plan new attacks against the u.S. And europe, diane. And there can't be enough security to protect all the workers there. Reporter: Exactly right. Very frightening situation. All right, brian. I know you'll bring us the latest news as you receive it.
This transcript has been automatically generated and may not be 100% accurate.