The death of a Kuwaiti fighter who fought alongside Saddam Hussein’s Iraqi regime has left the Islamic State group scrambling to find a replacement for Omar al-Bashir, the leader of its self-styled Islamic State of Iraq and Syria (ISIS).
Bashirs brother, Mohammed al-Shishani, who is fighting with the Iraqi security forces in Iraq’s Anbar province, is the most prominent and high-profile of the Iraqi fighters who fought under Bashirs command in Iraq.
But al-Sishani is no longer in Iraq and his fighters are no longer fighting for Bashirs forces.
Al-Sishes brother has been fighting for the group for months now and al-Douri, a member of the Jordanian national guard, has been one of the group’s top commanders.
In recent months, Jordanian authorities have arrested hundreds of Jordanian fighters who had fought in Iraq for the Islamic States and were later freed by Iraqi forces.
Al-Doura, a former member of a Jordanian elite unit, has since been named as one of five members of the top leadership of the al-Qaeda affiliate Jabhat al-Nusra, according to Jordanian intelligence officials and al Jazeera.
Al Doura is considered one of al-Assad’s most effective fighters, according the intelligence officials, and was the only Jordanian fighter to participate in the March 2016 suicide bombing of a Russian plane over Egypt’s Sinai Peninsula that killed 224 people.
“It’s a real loss for al-Baathism and the Syrian regime, and a real setback for the [Islamic State],” said Fadi al-Tamimi, a researcher at the Al Arabiya news website.
While the death of al Doura was announced early Tuesday, al-Sabah and the other Jordanian fighters were already dead by then, according, according.
The Jordanian military announced the death Monday, but did not elaborate on the circumstances of the killing.
Al Sabah’s commander, Colonel Ahmed al-Khaliq, told Al Jazeera that al-Doura was killed after the death threat against him.
Khalique, who was a member the Jordanian elite commando unit, said he and his men had received threats from al-Hassan al-Jabouri, the al Qaeda affiliate that al Qaeda’s chief Abu Bakr al-Muhajir has declared a caliphate.
Al Qaeda in Iraq, which has been accused of committing atrocities in Iraq by ISIS, had warned of al Sabah and al Khaliq’s imminent death.
“I am very worried about them, but I don’t know why, and I am also concerned about them in general, especially about their families,” Jabhat-al-Nusra spokesman Abu Omar al Adnani said in a statement released by al Qaeda in the Arabian Peninsula.
“They are all in hiding, and they don’t want to speak about what is happening to them.
This is the reason why we sent them the [email] that they have not been able to reply to.”
Al Sabahs sister in-law and father, Khaled al-Razi, told the AFP news agency the family was deeply saddened by the news.
“We all pray for the family, the brothers, the soldiers, and all the people who have suffered so much because of them,” he said.
Jabhat al Nusra is also known for killing hundreds of prisoners held in prisons in Iraq including those held for the past three years, according Abu Omar.
He said al Sabahs death was “a blow to the Syrian people and a blow to our people and the people of the world.”
In March 2016, al Qaeda fighters killed hundreds of Iraqi security personnel in the town of Tal Afar after the group stormed a military base in the Iraqi city of Fallujah.
Al Qaeda fighters seized control of Falluja that fall and continued the assault on Iraqi troops in the region.
Iraqi forces regained control of the city in September, but Iraqi forces have been unable to retake the town since then.
The al Qaeda-affiliated group was also responsible for the killing of U.S. special operations troops in 2014 and 2015.
Al Jazeera’s Ben Felt and Ibrahim Ghobari contributed to this report.