WASHINGTON * The two militant groups that claimed responsibility for the assault on the Radisson Blu Hotel in Mali are among the most dangerous and resilient in a hodgepodge of terrorist organisations in north-west Africa that have ties to nomadic tribesmen and Al-Qaeda.
One of the groups, Al-Mourabitoun, based in the ungoverned triangle of desert between Libya, Mali and Niger, was founded by Mokhtar Belmokhtar, the one- eyed mastermind of the 2013 terrorist seizure of an Algerian gas plant that left 38 foreign hostages dead. France's Defence Minister, Mr Jean-Yves Le Drian, said Belmokhtar was likely behind Friday's deadly attack.
The other group, Al-Qaeda in the Islamic Maghreb (AQIM), is the Al-Qaeda offshoot on the southern flank of the Sahara stretching from Senegal to Chad. Until Friday, it had been largely eclipsed on the militant landscape in Africa by Boko Haram in Nigeria and Belmokhtar's fighters. But the Al-Qaeda wing most likely still has millions of dollars in ransom payments from kidnapped Westerners, making it one of the wealthiest Al-Qaeda franchises.
More than 1,000 French troops and international forces had since early 2013 scattered these two groups, as well as other splinter factions, in Mali.
But the vicious attack in Bamako, the capital, is forcing counterterrorism officials to recalibrate the threat from this part of Africa, even as the West grapples with a more global menace from the Islamic State in Iraq and Syria (ISIS) after the attacks in Paris.
''Which faction did what is less important than the fact that these groups can still function even though the French have been there for two years hunting them down and killing them,'' said Mr Michael Shurkin, a former CIA analyst who is now at American non-profit global policy think-tank Rand. ''That tells me the problem is all but intractable and won't be solved easily or quickly.''
Boko Haram in Nigeria, which has pledged allegiance to ISIS, is perhaps the most violent group operating in northern Africa. And ISIS' affiliates in Libya pose the biggest long-term threat in the region, US officials said.
But at the centre of the terrorist groups is Belmokhtar, who has a long and complicated relationship with Al-Qaeda. Also known as Laaouar, or the one-eyed, after losing an eye to shrapnel, he fought against a Soviet-installed government in Afghanistan.
After returning to Algeria in the 1990s, he joined a militant Algerian group and took refuge in Mali, where he was involved in smuggling and kidnapping for ransom.
He became a leading figure in AQIM, when it was formed out of the Algerian group and took on its current name in 2007.
Belmokhtar's success in manoeuvring largely unhindered for years in the deserts of northern Mali, and southern Algeria and Libya, was a result of his masterful integration into the local populations. He is believed to have married a woman from the Timbuktu region of Mali, spoke the local dialects and shared some of his rich takings from more than a decade of kidnapping Westerners.
Mr J. Peter Pham, director of the Africa Centre at the Atlantic Council, a policy research group in Washington, said he was not surprised by the assault on the Radisson Blu Hotel.
''The militants have also shifted strategy away from attempting to seize and hold territory to attacking high-profile targets that has the double objective of hitting foreigners and garnering attention,'' Mr Pham said.
NEW YORK TIMES