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Story highlights

Pentagon: Sanafi al-Nasr, a Saudi citizen, killed in air strike by U.S.-led coalition in Syria

Nasr was the head of the Khorasan Group, said to be plotting attacks against the West

He is the fifth senior Khorasan Group leader killed in the last four months

(CNN) —  

The leader of an al Qaeda-linked group allegedly bent on attacking the West has been killed in an airstrike by the U.S.-led coalition in Syria, U.S. officials said Sunday.

Sanafi al-Nasr, a Saudi citizen whose real name is Abdul Mohsen Adballah Ibrahim al Charekh, was the highest-ranking member of the Khorasan Group – a collection of veteran al Qaeda jihadis which had moved into Syria, the Pentagon said in a statement.

He was killed in an airstrike in northwest Syria on Thursday, the statement said.

Nasr, who was once al Qaeda’s chief financial officer and had been designated a Specially Designated Global Terrorist by the U.S. Treasury, is the fifth senior Khorasan Group leader killed in the last four months, said the statement.

An image from Twitter of Sanafi al-Nasr, a top Khorasan Group leader killed in a strike in Syria.
From Twitter
An image from Twitter of Sanafi al-Nasr, a top Khorasan Group leader killed in a strike in Syria.

“The United States will not relent in its mission to degrade, disrupt and destroy al-Qaeda and its remnants,” said Secretary of Defense Ash Carter.

“This operation deals a significant blow to the Khorasan Group’s plans to attack the United States and our allies, and once again proves that those who seek to do us harm are not beyond our reach.”

Nasr’s death was referred to widely on jihadist social media sites, where he was mourned as a martyr.

’Significant blow’

Nasr had played a significant role in the group’s finances and had also been instrumental in organizing routes for new recruits to travel, via Turkey, from Pakistan to Syria, the Pentagon said.

“Al-Nasr was a longtime jihadist experienced in funneling money and fighters for al-Qaeda. He moved funds from donors in the Gulf region into Iraq and then to al-Qaeda leaders from Pakistan to Syria,” the Pentagon spokesman said in a statement.

CNN terrorism analyst Paul Cruickshank said the death of Nasr represented a “significant blow to al Qaeda,” as he was one of the terror group’s most senior figures in Syria.

“He was a highly influential strategist and prolific online propagandist and previously played key operational roles for the terrorist organization in the Afghanistan-Pakistan border region and Iran, including a stint in 2012 as al Qaeda’s chief financial officer,” he said.

Since relocating to Syria in 2013, he had become a leading figure in the al Nusra Front, an al Qaeda affiliate, said Cruickshank.

“He is believed to have worked to ensure the group remained within al Qaeda’s orbit and is also believed to have worked closely with deceased Khorasan Group leader Muhsin al Fadhli,” he said.

Fadhli, a Kuwaiti-born jihadi, was killed in a strike in Syria in July.

What is the Khorasan Group?

Khorasan’s existence wasn’t publicly acknowledged in the U.S. until last year, when U.S. director of national intelligence James Clapper said it was operating in Iraq and Syria with a focus on exporting terror to the West.

The Khorasan Group has actively plotted against U.S. and other Western targets, a senior U.S. official has said.

Former leader Fadhli fought alongside al Qaeda and the Taliban in Afghanistan and was among the few trusted al Qaeda leaders who received advance notification of the September 11 attacks, according to the Pentagon.

READ MORE: What is the Khorasan Group?

WATCH: Notorious French bomb-maker killed in strike

CNN’s Paul Cruickshank, Hamdi Alkhshali and Holly Yan contributed to this report.