In mid-September, as the U.S. military prepared to launch cruise missiles against Islamic State militants in Syria for the first time, CIA analysts lobbied to expand the target list to include eight possible locations for leaders of a band of battle-hardened Al Qaeda operatives moving between towns west of Aleppo.
The previously obscure Khorasan Group, believed to be led by a 33-year-old Kuwaiti named Muhsin Fadhli, was getting closer to being able to execute a terrorist attack on a passenger jet by concealing explosives in clothing or cellphones, the analysts feared. Fadhli reportedly moved to Syria last year to recruit European militants to launch terrorist strikes in the West.
Intelligence officials in Washington also worried that the group's leaders would stop using phones and other traceable devices once the bombing began. If they didn't hit the tight-knit cell and Fadhli in particular in the initial wave of airstrikes, the CIA analysts argued, they didn't know when they'd get another chance.
The CIA prevailed, and the analysts believed Fadhli was visiting one of the compounds in northwestern Syria that was pulverized in the opening salvo of 47 Tomahawks on Sept. 23. Early communications intercepts gave the CIA hope he had been killed.
But nearly two months later, U.S. spy agencies have not been able to confirm Fadhli's death, according to two U.S. officials briefed on the operation. The intelligence gap reflects far broader problems for the expanding U.S.-led air war against the heavily armed Islamic State fighters and others considered terrorists who have captured large parts of Syria and Iraq.
"It's a black hole," one U.S. official said, speaking on condition of anonymity in discussing intelligence, on the challenge of tracking terrorists and assessing casualties in a war zone that is in effect off-limits to U.S. personnel.
U.S. counter-terrorism officials have identified about a dozen Americans fighting with militants in Syria or Iraq, for example, including some who have joined Islamic State. But U.S. intelligence analysts have struggled to develop a complete picture of their movements or what roles they play in the militant groups.
U.S. intelligence agencies have poured resources into the war since the spring, and the CIA has set up a training camp in Jordan for Syrian fighters. They also rely on information gathered from U.S.-backed rebel groups, including the Free Syrian Army.
The White House now is considering expanding the CIA's role in arming and training fighters deemed friendly, the Washington Post reported Saturday. The clandestine operation now vets and trains about 400 fighters a month, but the CIA-backed factions have struggled to take and hold territory. In one recent battle, they fled positions in a battle with Al Nusra Front, abandoning their weapons to the group, which is Al Qaeda's affiliate in Syria.
So far, U.S. aircraft have launched at least three raids on targets associated with the Khorasan Group. U.S. officials say the network operates in coordination with Al Nusra Front and poses a direct terrorist threat to the United States and its allies, although some counter-terrorism experts in the region question that analysis.
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CIA intelligence gap hinders counter-terrorism efforts in Syria, Iraq