Morell: 'Real Value' in Removing ISIS Operative From Battlefield

It would have been good if U.S. forces were able to capture Abu Sayyaf, the man described as the Islamic State's head of oil operations, alive, former CIA Director Michael Morell said Sunday, but there is "real value" in removing him from the conflict.

"The real value here is taking a guy off the battlefield who's incredibly important to the organization, to funding it, to running it, [and is] very close to the senior leadership, Morell told ABC News "This Week" host George Stephanopoulos.

On Saturday, U.S. Army commandos launched a rare ground attack in Syria, killing Sayyaf and capturing his wife, Umm Sayyaf, who remains in custody. The Delta Force commandos also rescued a woman that American officials said was being enslaved at the location.

A U.S. defense official said the commandos slipped across the Iraqi border aboard Black Hawk helicopters and V-22 Osprey aircraft with the intention of capturing Abu Sayyaf, but after a firefight ensued, the militant was killed, along with about a dozen ISIS fighters.

"It would have been great to keep him alive," Morell said, "But his wife worked closely with him. She'll be able to tell us a lot."

Further, computers and information that were seized are "going to help us understand the organization better," Morell said.

In October, a U.S. Treasury official said ISIS was earning about $1 million a day from the black market sales of oil. U.S.-led coalition airstrikes have been going on since September to target ISIS-controlled oil-collection sites in hopes of undermining the militant group's finances.

Morell on Sunday said that his greatest fear where ISIS is concerned is the growing threat of an attack in the homeland "using some sort of weapons of mass destruction."

"If they get a safe haven and they get it over the long term, those are the kind of things we have to worry about," said Morell, who noted that about 25 percent of the territory ISIS took in Iraq has been reclaimed.

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