Pentagon 'Reasonably Certain' 'Jihadi John' Was Killed in Drone Strike

— -- The U.S. is "reasonably certain" that "Jihadi John" was killed in a U.S. drone strike in Raqqa, Syria, on Thursday night, according to a U.S. military spokesman. Though the U.S. is still working to conclusively determine that he was killed in the strike, the official characterized his death as a "significant blow" to ISIS given his prominence as a major recruiting tool for the organization.

"It’s still early, but we are reasonably certain that we killed the target that we intended to kill, that was 'Jihadi John,'" said Colonel Steve Warren, the U.S. military spokesman in Baghdad in a video briefing with Pentagon reporters.

"Jihadi John" was the nickname used to describe Mohammed Emwazi, a British member of ISIS, who gained notoriety for his role in the beheading videos of Western hostages.

A U.S. military drone fired a Hellfire missile at a car carrying Jihadi John and another person, Warren said. A U.S. official told ABC News that three MQ-9 Reaper drones were involved in the mission targeting "Jihadi John," two of them American drones, the other a British one. Two Hellfire missiles were fired by one or two of the American drones and the British drone did not fire missiles, the official said.

"We know for a fact that the weapons system hit its intended target and that the personnel who were on the receiving end of that weapons system were in fact killed," said Warren. "We still have to finalize the verification that those people were specifically who we thought they were."

"We had been following this target for some time," Warren said, and intelligence indicators gave the U.S. "great confidence" that the individual targeted in the strike was Jihadi John. "When the opportunity presented itself, the opportunity for minimal civilian casualties, we took the shot."

"He was somebody who was an ISIL leader, a strategist for that organization, somebody who was actively involved in their online recruitment and radicalization efforts," White House spokesman Josh Earnest said, referring to the other name for ISIS. "That made him a target worth going after.”

Warren described Jihadi John's death as "a significant blow" to ISIS because he was so well known and "kind of the face of the organization in many senses."

"His death is more significant for ISIL -- he was a primary recruitment tool for that organization," Warren said.

A U.S. official agreed with that assessment, noting that though "Jihadi John" was not a major operational figure for ISIS, his death would have an impact on ISIS given his high visibility as a recruiting tool.

Despite his notoriety, "Jihadi John" had not appeared publicly for quite some time. The official said that was because about a year ago ISIS leaders told him to “tone down” his profile. He remained heavily involved in the group’s recruitment and public relations efforts but from behind the scenes.

A U.S. military official told ABC News that the U.S. is "99 percent certain" that Jihadi John is dead based on the intercepts of communications by ISIS extremists in the wake of the strike. The official said that in one communication there was an instruction to “stop talking about this,” which is a good indicator that he was killed in the strike.

There was also good intelligence gathered before the strike that placed him in the car that was struck.

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