Al-Nusra Military Commander Is Killed in a Mystery Airstrike

Al Qaeda affiliate Jabhat al-Nusra has confirmed that its military commander was killed by a suspected airstrike in Syria's northwestern Idlib province along with three others.

Abu Hommam al-Shami was reported to have been killed on Thursday by the UK-based Syrian Observatory for Human Rights (SOHR), as well as Syria's state-controlled SANA news agency.

Social media channels linked with the group subsequently confirmed the news. Then al-Nusra spokesman Abu Anas al-Shami (both men took a nom de guerre which ends in the Arabic for "the Syrian") admitted that Abu Hommam was dead, adding that two of his bodyguards were also killed, in a statement posted on Jihadi websites, according to AP.

Twitter accounts named the other three senior leaders as Abu Musab Falastini, Abu Omar Kurdi, and Abu Baraa Ansari, the BBC reported.

It is not yet certain who actually carried out the airstrike. SANA said the Syrian air force was responsible, but al-Nusra supporters and members blame the US-led coalition that has been launching airstrikes in Syria since September primarily intended to "degrade and destroy" the Islamic State militant group.

Washington also lists al-Nusra as a terror group, however, and targeted it with a limited number of attacks in 2014, though has left it largely unmolested since then. Syria's many insurgent groups have also targeted rival leadership with IEDs in the past.

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The attack also came few days after al-Nusra forced the dissolution of Washington's favored Syrian rebel group, called Hazm Movement or Harakat Hazm. This secular militia had been supplied with advanced US weapons and training as part of a covert CIA program.

Hazm announced over the weekend that it would disband after al-Nusra captured its Aleppo province headquarters. Its members will now be absorbed by a newly formed rebel coalition called the Shamiyah Front, which includes more moderate factions alongside hardline Salafists. Fighters with al-Nusra later claimed on Twitter to have taken large supplies of weapons along with the Hazm base.

The al Qaeda affiliate had already pushed Hazm and the allied Syrian Revolutionaries Front out of Idlib province in November 2014. At the time, social media accounts linked with al Nusra again said that US weapons were among a large cache of arms and equipment seized by the militants.

This attack also came just after al-Nusra launched a major offensive in Aleppo, including a large attack on the city's Air Force Intelligence headquarters. The assault began on Wednesday when the group detonated a large quantity of explosives in a tunnel underneath the premises before launching a ground assault that was ultimately pushed back by government troops. Clashes continued well into Thursday, with heavy casualties on both sides, according to SOHR.

A number of recent reports have suggested that al-Nusra, which is also on the UN Security Council's sanctions list, may be considering breaking off from al Qaeda in exchange for increased support from Gulf states, which oppose both Assad and Islamic State.

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Follow John Beck on Twitter: @JM_Beck