According to Jean-Pierre Filiu, a French scholar who has extensively studied AQIM, Belmoktar rose steadily through the ranks to become the GIA commander for the Sahara.

CNN: STORY HIGHLIGHTS

To make money, "Belmoktar increasingly engaged in smuggling, earning the popular nickname 'Mr. Marlboro' ... he also was involved in the smuggling of drugs, weapons, and illegal immigrants, " Jean-Pierre Filiu in a 2010 Carnegie Paper.

CNN: STORY HIGHLIGHTS

"He appears to have drifted into a parallel world where he picked and chose elements to build himself a new identity, " said Jean-Pierre Filiu, a professor in the Middle East department at the Paris Institute of Political Studies.

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