“Al Qaeda remains a global force with its networks and branches around the world,” Ambassador Nathan A. Sales, the State Department’s counterterrorism coordinator, said in a conference call with reporters on Wednesday after releasing the department’s annual country reports on terrorism.
Mr. al-Aruri, who was also known as Abu al Qassam, was a close companion and brother-in-law of Abu Musab al-Zarqawi, the Jordanian terrorist who headed Al Qaeda in Mesopotamia until he was killed by an American airstrike in Iraq in 2006, according to Thomas Joscelyn, a senior editor of FDD’s Long War Journal, a website run by the Foundation for Defense of Democracies that tracks military strikes against militant groups.
In 2015, Mr. al-Aruri was one of five senior Qaeda figures freed by Iran in exchange for an Iranian diplomat held in Yemen. His release brought a highly experienced operative back to the field, and after his arrival in Syria he slowly climbed the ranks to become Al Qaeda’s military boss and then the de facto leader there.
The new Qaeda branch, called Hurras al-Din, emerged in early 2018 after several factions broke away from a larger affiliate in Syria. It is the successor to the Khorasan Group, a small but dangerous organization of hardened senior Qaeda operatives that Ayman al-Zawahri, Al Qaeda’s leader, sent to Syria to plot attacks against the West.
The Khorasan Group was effectively wiped out by a series of American airstrikes several years ago. But with as many as 2,000 fighters, including seasoned leaders from Jordan and Egypt, Hurras al-Din is much larger and has operated in areas where Russian air defenses have largely shielded them from American airstrikes and the persistent stare of American surveillance planes.
Moscow dispatched military aid and advisers to Syria in late 2015 to support the beleaguered government of President Bashar al-Assad.
Hurras al-Din was initially led by Abu Hammam al-Shami, another Qaeda veteran, but a United Nations report said last year that Mr. al-Aruri took charge of the organization at some point.