Washington: The Islamic State group’s battle-tested equivalent of a defense minister is believed to have been killed in a US air strike in Syria, a US official said on Tuesday.

The target of the 4 March attack was Omar al-Shishani, a Georgian fighting with the jihadist group in Syria, the Pentagon said in a statement. It said the result of the attack was still being assessed.

But a US official speaking on condition of anonymity later said al-Shishani ‘likely died’ in the assault by waves of US warplanes and drones, along with 12 other IS fighters.

Al-Shishani is the nom de guerre of Tarkhan Batirashvili, a Georgian with a $5 million US bounty on his head. He is also known for his flowing red beard.

His death, if confirmed, would hinder IS’s foreign recruitment efforts and its attempts to defend its strongholds in Syria and Iraq, the Pentagon statement said.

Al-Shishani was ‘the ISIL equivalent of the Secretary of Defense,’ the US official said, using an alternative acronym for the Islamic State group.

The US Treasury designated him a foreign terrorist fighter in 2014, and said he maintained ‘unique authority’ within IS.

Batirashvili comes from a town in Georgia that is populated mainly by ethnic Chechens, the official said.

He fought as a Chechen rebel against Russian forces before joining the Georgian military in 2006, and fought Russian forces again in Georgia in 2008.

After being discharged from the Georgian military on health grounds he entered Syria in 2012 and joined IS the next year, the official speaking on condition of anonymity said.

Among his feats on his way to the top ranks of Islamic State military operations, the official said, Batirashvili turned one rebel group into an effective fighting force to take on the Syrian army by ‘mixing Syrians who knew the terrain with the Chechens’ fighting ability.’ 

In the recent assault, waves of US aircraft struck near Al-Shadadi, a town in northeastern Syria that was retaken from IS last month by local anti-IS fighters allied with the US-led coalition.

The US official said it was ‘unusual and noteworthy’ that Batirashvili had travelled from the Islamic State group’s self-proclaimed capital of Raqa to Al-Shadadi.

‘This was likely to bolster the sagging morale of ISIL fighters there, who have suffered a series of defeats by Syrian Democratic Forces,’ the official said, alluding to one of the local, US-allied fighting groups.

The Pentagon statement described Batirashvili as ‘a battle-tested leader with experience who had led ISIL fighters in numerous engagements in Iraq and Syria.’

If he did in fact die in the assault, his absence will especially hinder IS’s ability to recruit foreign fighters from Chechnya and the Caucasus regions, Cook said in the statement.

It would also undermine the group’s ability to coordinate attacks and defend strongholds like Raqa, Syria, and Mosul in Iraq, it added.