It's divided between Syrian and "rebel" forces, but the rebel forces only lost ground to the IS in the last few weeks--after the rebels were weakened Russian airstrikes.

It's primarily other Islamist factions, most of which fight the IS rather brutally, which compose the ranks of the "rebels".

Only Russia (and Syria, but I repeat myself) say that Russia targets only the IS. For Russia, the enemy's identification is a matter of convenience and necessity, not accuracy and veridicality. (They have the same attitude towards the identification of their own forces. "Those troops aren't ours, no, they're not ours." A day later, "Look at what our troops did, we're giving them medals." Again, the past is really hard to predict in Russia. It's only the future that's easy to predict.)

"It's primarily other Islamist factions, most of which fight the IS rather brutally, which compose the ranks of the "rebels". "

"Islamists factions" indeed. The real moderate and secular Syrians are fleeing Assad, Isis, and these "rebel Islamist factions" in the millions to seek safety and human rights in Europe -- they don't see the "islamist factions" we are backing as a reasonable alternative to ISIS or Assad.

http://news.yahoo.com/syria-army-allies-advance-near-aleppo-russian-cover-144740103.html

Beirut (AFP) - Syrian regime forces edged forward in the northern province of Aleppo on Saturday with air cover from Russian warplanes, but faced fierce resistance from rebel forces in the country's centre.

Since Moscow began its air campaign in support of its Damascus ally on September 30, the army and its allies have launched four ground offensives against rebel forces in northern and central Syria.

Syrian troops have gone on the attack in Aleppo, Hama, Homs and Latakia provinces taking advantage of Russian air strikes against Al-Qaeda affiliate Al-Nusra Front and other rebel groups.

Three senior Nusra members, one of them a US-designated "global terrorist", were killed in an air strike in Aleppo province on Thursday, a monitoring group said.

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