Jihadists made advances on opposition militants in the battle for Raqqa, in northern Syria, but are on the back foot in parts of Aleppo and Idlib.
An Aleppo-based activist "In Idlib and Aleppo provinces, the al-Hr militia is advancing, but in Raqqa the Islamic State of Iraq and the Levant (ISIL) is winning because its supply routes to Iraqare open there", adding that "in Idlib there are practically no ISIL bases left, as is the case in Aleppo city and the west of the province".
Opposition Observatory said that in Raqqa, which came under ISIL's control soon, "ISIL seized the Mashlab district and an al-Nusra Front base" on Thursday night
While opposition militants initially welcomed the jihadists in Syria, ISIL's horrific abuses and quest for hegemony has turned "90 percent of people" in opposition areas against the group.
Fighting pitting ISIL against other opposition groups - including al-Nusra Front, which is also linked to Al-Qaeda -broke out last Friday.
Hundreds of fighters on both sides have since been killed, according to the Britain-based opposition observatory.