The al-Nusra Front, an al-Qaeda affiliated militant group in Syria, attacked the government-held city of Idlib Monday and briefly seized a number of state buildings, the BBC reported.
Government forces blocked the offensive, pushing back the rebels, who claimed had killed dozens of regime soldiers.
Syrian government forces have maintained control of Idlib since the north-western city was briefly taken by rebel groups in 2012.
The Nusra Front launched its offensive on the town from all sides, the Syrian Observatory for Human Rights (SOHR), a London-based group monitoring the conflict in Syria, said.
While most of the attacks took place in the south of the city, the rebels stormed checkpoints and briefly took control of governor's office and a police headquarters.
The militants also seized a hill that would have given them some strategic advantage, provoking the government to deploy helicopter gunships, which reportedly killed dozens of rebels and soldiers.
As the world’s attention is fixated on U.S.-led coalition airstrikes against ISIS targets, the Nusra Front continues to slowly advance in the north west and south of Syria, according to the BBC’s Jim Muir in Beirut.
A buffer against extremist rebels
The Free Syrian Army (FSA), a group of moderate rebels the U.S. said it wants to train and equip, is one of the few buffers against extremist-rebel groups such as ISIS and the Nusra Front.
However, the U.S. representative to the anti-ISIS coalition said he sees the FSA as a crucial part of a political solution, rather than a military one, to end the war.
Asked whether those rebel FSA units would ultimately go on to fight Syrian government forces, John Allen, the U.S. representative to the coalition, told the Asharq al-Awsat daily:
“No. What we would like to see is for the FSA and the forces that we will ultimately generate, train, and equip to become the credible force that the Assad government ultimately has to acknowledge and recognize.”
“There is not going to be a military solution here,” he added, in comments published at the weekend on the newspaper's English language website.
The Free Syrian Army is a term used to describe dozens of armed groups fighting to overthrow Assad but with little or no central command. They have been widely outgunned by Islamist insurgents such as ISIS.
Allen said there was a need to build up the credibility of the moderate Syrian opposition at a political level, adding that it was normal for rebel forces to clash with the Syrian military as they seek to defend their territory and families.
“But the intent is not to create a field force to liberate Damascus — that is not the intent,” Allen, a retired U.S. general, told the newspaper.
“The intent is that in the political outcome, they must be a prominent - perhaps the preeminent voice - at the table to ultimately contribute to the political outcome that we seek,” he said at the start of a Middle East tour.SHOW MORE