A one-eyed veteran Islamist guerrilla and smuggler - known as "The Uncatchable" to French intelligence and "Mr Marlboro" for his illicit cigarette empire - has been named by Algerian officials as the man behind the oil field kidnapping.
Algerian Interior Minister Daho Ould Kablia identified Sahara warlord Mokhtar Belmokhtar as the leader of the hostage takers.
Belmokhtar, who is in his early 50s, has been linked to multiple kidnappings of foreigners in North Africa in the last decade, including the taking of 32 European tourists in 2003.
An Algerian court sentenced Belmokhtar in absentia to a life sentence for his role in the killing of 10 Algerian custom agents in 2007.
Still on the run, the Saharan Jihadist, who is also known as Khaled Abou Al Abbas, has built up a reputation as one of the most daring and elusive Islamic jihadist leaders.
Only last year, Algerian media reports of his death in violence in the rebel-held town of Gao in northern Mali proved unfounded.
The New York Times has reported Belmokhtar is believed to have masterminded this week's oil field attack from the town, which has been attacked by French warplanes.
After fighting Soviet forces in Afghanistan in the late 1980s, Belmokhtar set up his own group in the Sahara after falling out with other local al Qaeda leaders.
Belmokhtar, who was born in Ghardaia, Algeria in 1972, earned the moniker "Mr Marlboro" in the Saharan region for his illicit cigarette-running business, which he uses to fund his jihad.