Killing of Key Syria Rebel Chiefs Deals Opposition Blow

A blast has wiped out the leadership of a pragmatic Islamist rebel brigade in Syria, dealing a new blow to the country's armed opposition that could splinter its most important coalition.

Late Tuesday 47 members of Ahrar al-Sham's leadership were killed when a blast hit a meeting of its top religious and military chiefs in the northeastern province of Idlib, including its chief Hassan Abboud, known by the name Abu Abdullah al-Hamawi.

No group has claimed the blast and Ahrar al-Sham has yet to officially blame any party for the attack.

Instead it moved quickly to name new leaders, designating Hashem al-Sheikh, also known as Abu Jaber, to replace Abboud as Ahrar's chief, and Abu Saleh Tahhan as his military chief.

The group is one of the oldest and largest of Syria's armed opposition groups, established in 2011 by Islamists released by the Syrian regime early in the uprising against President Bashar Assad.

It is also the most important part of the key Islamic Front rebel coalition, which has battled Assad's regime and jihadists from the Islamic State group, expelling it from parts of northern Syria.

The fate of that coalition could now hang in the balance, experts said.

"The most significant consequence is that the fate of the Islamic Front now looks desperate," wrote Charles Lister, a visiting fellow at the Brooking Doha Center, in an analysis of the attack.

The coalition could now splinter between more moderate elements, who could drift towards Western-backed rebel brigades, and more radical members and factions, who could join either the Islamic State or al-Qaida-affiliate al-Nusra Front.

Ahrar al-Sham -- said to group together some 10,000 to 20,000 fighters -- has always espoused a conservative Islamist bent, openly seeking the establishment of an Islamic government in Syria and working alongside al-Nusra on various battlefronts.

But the group never backed the transnational jihadist ideology of the Islamic State and was often seen as a bridge between more moderate and radical strands of the opposition.

Lister said the new leadership could shift that balance.

"It would seem Ahrar al-Sham's senior leadership has lost a balance it previously managed between moderates and hardliners, with the latter now more openly dominant," he wrote.

Aron Lund, an expert on the Syrian conflict writing for the Carnegie Endowment for International Peace, echoed the assessment of the Islamic Front's fragility.

"Unless Ahrar al-Sham somehow manages to recover and sustain its relevance as a major Islamist faction, the Islamic Front may now be beyond repair," he wrote.

That splintering could paradoxically benefit both groups more moderate and more radical than Ahrar al-Sham, he said.

"Leaderless fighters can spill either way. Some may opt for FSA-aligned factions." he said, referring to the Western-backed Free Syrian Army.

"But more committed Salafis (conservative Islamists) may find the Nusra Front more to their liking. Others still could decide to join the Islamic State," Lund said.

Militarily, experts said the group's decapitation was unlikely to have immediate consequences for either the battle against the regime or the Islamic State.

But both would stand to benefit, experts said.

IS "is the principal beneficiary of the killings," said Noah Bonsey, a senior analyst on Syria at the International Crisis Group.

"Ahrar al-Sham is a key component of anti-IS rebel forces in the north, and ISIS will aim to exploit any potential unraveling," he said.

Syria's government, meanwhile, "has an interest in weakening the rebels so it can present itself to the West as the sole obstacle facing the Islamic State," added Thomas Pierret, a Syria specialist at the University of Edinburgh.

Pierret said the implications for the United States were more complex.

The United States has never backed the group, so its weakening "is not necessarily bad news for Washington," he said.

But in the mid-term, the attack could stand to complicate U.S. efforts to tackle IS, he added.

"It could remove from the military equation a key part of the anti-IS coalition, and it is possible that part of Ahrar's base will join the Islamic State," he told Agence France-Presse.

In his first address after being named chief on Wednesday, Ahrar al-Sham's new leader Abu Jaber appeared to make reference to the risk of the group's disintegration.

"Don't lose hope because hopelessness is destructive," he said in a video message.

"Don't let this catastrophe shake your confidence and scatter you."