The leader of the so-called Islamic State group, Abu al-Hassan al-Hashimi al-Qurayshi, was killed in battle recently, the group’s spokesman has said.

Al-Qurayshi is the second IS leader to be killed this year at a time when the extremist group has been trying to rise again, with its sleeper cells carrying out deadly attacks in Iraq and Syria. Its affiliate in Afghanistan also claimed attacks that killed dozens in recent months.

The US military said al-Qurayshi was killed in mid-October, adding that the operation was conducted by Syrian rebels in the southern province of Daraa. It was not clear why the announcement was made on Wednesday, more than a month after al-Qurayshi was killed.

“Isis remains a threat to the region,” the US Central Command said. “CENTCOM and our partners remain focused on the enduring defeat of Isis.”

The Britain-based Syrian Observatory for Human Rights, an opposition war monitor, reported in mid-October, that Syrian rebels who had earlier reconciled with the government killed a group of IS fighters in the southern village of Jassem in Daraa province.

They included a commander identified as an Iraqi citizen along with a Lebanese fighter and others, the observatory said, adding that one of the IS fighters detonated an explosive belt he was wearing during the clash.

Little had been known about al-Qurayshi, who took over the group’s leadership following the death of his predecessor, Abu Ibrahim al-Hashimi al-Qurayshi, in a US raid in February in north-west Syria.

None of the al-Qurayshis are believed to be related. Al-Qurayshi is not their real name but comes from Quraish, the name of the tribe to which Islam’s Prophet Mohammed belonged. IS claims its leaders hail from this tribe and “al-Qurayshi” serves as part of an IS leader’s nom de guerre.

The death marked a blow to the group that was defeated in Iraq in 2017 and in Syria two years later. The announcement by IS spokesman Abu Omar al-Muhajer came at a time when IS has been trying to carry out deadly attacks in parts of Syria and Iraq the extremists once declared a caliphate.

“He died fighting the enemies of God killing some of them before being killed like a man on the battlefield,” al-Muhajer said.

Al-Muhajer said Abu al-Hussein al-Husseini al-Qurayshi was named as the group’s new leader.

“He is one of the veteran warriors and one of the loyal sons of the Islamic State,” al-Muhajer said. Little is also known about Abu al-Hussein al-Husseini al-Qurayshi.

Asked in Washington about al-Qurayshi’s death, the spokesman for the US National Security Council, John Kirby, said: “We certainly welcome the news of the death of another Isis leader. I don’t have any additional operational details to provide at this time.”

Al-Qurayshi is the third leader to be killed since founder Abu Bakr al-Baghdadi was hunted down by the Americans in a raid in October 2019.