By Weedah Hamzah and Pol O Gradaigh, dpa

BEIRUT — One of Syria’s largest rebel groups hurriedly named new commanders after its leadership was wiped out in an explosion, hours before the U.S. president was to outline a plan to combat the Islamic State and discuss support for the moderate Syrian opposition.
In a major blow to Syria’s beleaguered rebels, who are caught between resurgent government forces and advancing Islamic State jihadists, some 50 members of Ahrar al-Sham were killed in an explosion in Idlib province on Tuesday night, the Syrian Observatory for Human Rights said.
Ahrar al-Sham is among the rebel forces fighting against the Islamic State group, which has taken control of large swathes of territory in northern and eastern Syria and in neighbouring Iraq.
Ahrar al-Sham and its allies in the Islamic Front — one of Syria’s largest rebel coalitions — have also played a key role in fighting against President Bashar al-Assad’s forces.
Hashim al-Sheikh Abu Jaber would replace Hassan Abboud as overall commander, the group announced. Abboud was also head of the Islamic Front’s political bureau. There was no immediate indication of his replacement in that role.
Later Wednesday, U.S. President Barack Obama is to outline a strategy against the Islamic State in Iraq and Syria and providing support for the moderate Syrian opposition.
And on Thursday, the new U.N. envoy to Syria, Staffan de Mistura, is to meet al-Assad in Damascus, the al-Watan newspaper reported.
Analyst Aron Lund wrote for the Carnegie Endowment for International Peace that “the list of dead [in the blast] reads like a who’s who of Ahrar al-Sham leaders.”
Ahrar al-Sham issued a defiant statement vowing to continue the fight against al-Assad’s forces as well as Islamic State “until the people of Syria are delivered from them both.”
Lund wrote: “Of course, there may still be influential but unknown figures left who could step into the void and prevent Ahrar al-Sham from fracturing. But if not, it seems that one of Syria’s most important rebel groups has been decapitated.”
The cause of the blast remained unclear. The Islamic Front’s initial statement announcing the “martyrdom” of Abboud said the rebels were killed by a car bomb as they held a meeting.
Syria analyst Charles Lister, writing for the Huffington Post, said that “the most likely scenario appears to be that a government airstrike targeted the meeting, which was taking place in an underground bunker.
“The airstrike set fire to an attached ammunitions depot, which consequently meant the bunker was filled with acrid smoke, causing suffocation. An apparent lack of bodily wounds on the victims’ bodies would appear to fit this account,” Lister wrote.
The Islamic State, which has fought rebels including Ahrar al-Sham since the beginning of this year, has previously used car bombs and suicide attacks to target the leaders of rival groups.
Abboud himself had accused the Islamic State of a February blast that killed Ahrar al-Sham’s Abu Khaled al-Suri, a jihadist believed to have personal links to al-Qaeda’s leadership.
Al-Suri had fought against U.S. troops in Afghanistan and Iraq. The U.S. government described him as al-Qaeda’s representative in Syria.

AFP Photo/Zein al-Rifai

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