Syrian Rebel Groups Launch Largest Offensive in Years

Syrian opposition forces have launched an offensive in western Aleppo district that has killed at least 89 people and overtaken a Syrian military base, a monitoring group based in Britain reported on Wednesday.

The attacks are the most notable escalation in the Syrian conflict in years, expert say.

Fighters from various rebel factions, including a group linked to Al Qaeda called Hayat Tahrir al-Sham, had advanced by Wednesday to within about six miles of Aleppo and taken over weapons and vehicles previously held by forces loyal to the government of President Bashar al-Assad, according to the monitoring group, the Syrian Observatory for Human Rights.

Opposition factions announced on the Telegram messaging app that they had taken Base 46, the largest Syrian government base in the area, as well as tanks, and had captured members of the pro-government forces on Wednesday. They also announced that they had taken over a number of villages in the countryside west of Aleppo district.

“In the matter of about 10 hours, a wide spectrum of armed opposition groups have managed to get to within about four or five kilometers now of Aleppo city, which is of gigantic significance,” Charles Lister, the director of Middle East Institute’s Syria and counterterrorism programs, said on Wednesday.

The Syrian government did not immediately respond to a request for comment.

The attacks are believed to be the first major effort since 2020 by the rebel groups to take territory, when Turkey, which sided with the opposition forces, and Russia, which is Syria’s ally, brokered a cease-fire to halt fighting in the Idlib region.

The recent escalation is part of increasing volatility in the region, experts say.

“Pro-regime militias have been upping their attacks in the area, trying to deter the rebels because Israel has been weakening the Syrian regime’s allies like Hezbollah and Iran,” said Natasha Hall, a senior fellow with the Middle East Program at the Center for Strategic and International Studies.

The success of the offensive thus far shows the vulnerability of the Syrian government and the growing prowess of the various opposition factions, experts say.

“Years ago, an offense of this size would have been pushed back by the regime,” Mr. Lister said. But opposition forces like Hayat Tahrir al-Sham, which traces its origins from the Qaeda affiliate Jabhat al-Nusra, have invested heavily in resources and training for night operations. “That basically levels the playing field,” he added.

Dr. Mustafa Aledou, a pharmacist and program manager for MedGlobal, a Chicago-based nonprofit, lives in Idlib city and said he was less than 20 miles from the attacks.

His family woke early in the morning to the sound of bombing, he said.

“We can hear the explosions,” he said. “We can hear the attacks in the battle in the frontline between the fighting forces.”

The local authorities announced the closure of schools and large markets because of the fighting.

Milana Mazaeva contributed research.