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Story highlights

The "Emir" of ISIS-K was killed on July 11, according to the Pentagon

Abu Sayed's death marks the third time an ISIS-K leader has been killed within a year

(CNN) —  

The Pentagon said Friday that US forces have killed Abu Sayed, the leader of ISIS-Khorasan, the terror group’s Afghanistan affiliate.

The “Emir” of ISIS-K was killed “in a strike on the group’s headquarters in Kunar Province, July 11,” Chief Pentagon spokesperson Dana White said in a statement.

US Navy Captain Bill Salvin, spokesman for US Forces Afghanistan provided additional detail of how Abu Sayed was killed. Salvin said he was killed in an airstrike by a US drone. The initial Pentagon statement described Sayed being killed in a “raid”. 

Secretary of Defense James Mattis told reporters on Friday that the death of  a leader like Sayed “sets them back for a day a week, a month, it’s about who it is and what kind of people are below them. It is obviously a victory on our side in terms of setting them back, it’s the right direction.”

Gen. John Nicholson, Commander, US Forces Afghanistan said in a statement, “This operation is another success in our campaign to defeat ISIS-K in Afghanistan in 2017. Abu Sayed is the third ISIS-K emir we have killed in the last year and we will continue until they are annihilated. There is no safe haven for ISIS-K in Afghanistan.”

Hafiz Sayed Khan was killed in July 2016 and another emir Abdul Hasib was killed during a joint US-Afghan commando raid in April.

April’s raid also resulted in the deaths of several other high ranking leaders of ISIS-K, the terror group’s regional branch, and 35 ISIS fighters. Two American soldiers died in the attack, perhaps from friendly fire, military officials said at the time.

The presence of Sayed in Kunar is noteworthy, the other two leaders were killed in neighboring Nangarhar province the terror organization’s traditional powerbase.

Afghan and US forces launched a counter ISIS-K offensive in early March 2017 and Gen. John Nicholson, the commander of US and NATO troops in Afghanistan, has pledged to drive the terror group out of Afghanistan by the end of 2017.

Unlike elsewhere in Afghanistan where US troops primarily serve a training and supporting role, US special operations forces have been directly engaged in the offensive against ISIS in Afghanistan, conducting raids and strikes in the country’s eastern provinces.

CNN’s Barbara Starr contributed reporting