The second-in-command of al-Qaeda has been killed in a US drone strike in Syria, according to jihadist reports.
If the death of Abu al-Khair al-Masri is confirmed it would be a major blow to the terror group and the biggest loss to its leadership since the killing of Osama bin Laden in 2011.
His killing would also be a victory for the Trump Administration one month after a botched US raid in Yemen that left an American commando and many Yemeni civilians dead.
Neither al-Qaeda nor the US has officially confirmed that the 59-year-old Egyptian jihadist was killed by an American strike in Idlib province yesterday.
But reports of his death spread widely among jihadist groups and social media accounts, according to the Site Intelligence Group, which monitors extremist groups.
Sherif Hazzaa, an Egyptian jihadist, said that al-Masri was dead and that he had spoken to him only a few days before in Syria. "He told me days ago: I do not carry my gun because I'm expecting to be targeted by a plane," Hazzaa said on Twitter.
Photographs circulating on social media purported to show the car that al-Masri was driving in when he was killed. They showed a grey car with its roof blown open by an apparent strike from above.
At least one bodyguard was also reported to have been killed in the strike.
If al-Masri is dead it would mark a bloody end to a long career in jihadism and a significant loss for al-Qaeda not just in Syria but in its global operations.
Al-Masri was one of the few prominent living al-Qaeda leaders of pre-9/11 era.
He was married to one of bin Laden's daughters and ran a guesthouse in Afghanistan where elements of the September 11 attacks were planned, according to the Soufan Group intelligence group.
"[His] significance in terms of his direct connection to the core of al-Qaeda and to some of its more infamous attacks is difficult to overstate," the group said.
After the US-led invasion of Afghanistan in 2001, Al-Masri and other leading al-Qaeda members fled into neighbouring Iran.
Iran has had a complicated relationship with Sunni jihadist groups like al-Qaeda, sometimes sheltering them against the US while also wary of their fundamentalist ideology.
Al-Masri and several others, along with their families, were essentially placed under house arrest by the Iranians and prevented from leaving Tehran.
He and four other al-Qaeda figures were freed in 2015 as part of a prisoner swap, according to the New York Times. The terror group released an Iranian diplomat kidnapped in Yemen in return.
Al-Masri appears to have headed to Syria soon after his release to take charge of al-Qaeda's increasingly ambitious affiliate there, known then as the al-Nusra Front.
With al-Masri's blessing al-Nusra split from the main al-Qaeda organisation and rebranded itself in an effort to appear as a more domestically Syrian group.
Western officials said the split was little more than a cosmetic move and that al-Nusra retained its al-Qaeda beliefs even as it operated under a different name.
Al-Masri is a nom de guerre that literally means "the Egyptian".
He is believed to have been born in Egypt under then name Abdullah Mohammed Rajab Abd al-Rahman and to have in the Egyptian Islamic Jihad group before joining al-Qaeda.