Beirut. The Syrian military rushed in reinforcements and struck Idlib city Sunday in an attempt to push back insurgents from advancing farther after seizing Aleppo and surrounding strategic locations in an adjacent province in a surprise offensive.

The insurgents led by Hayat Tahrir al-Sham took over most of Aleppo on Saturday and claimed to have entered the city of Hama. There was no independent confirmation of their claim.

The swift and surprise offensive is a huge embarrassment for Syrian President Bashar Assad and raises questions about his troops' preparedness. It also comes at a time when Assad’s allies — Iran and groups it backs and Russia — are preoccupied with their own conflicts.

Iranian Foreign Minister Abbas Araghchi travels to Syrian capital Damascus later Sunday. He told reporters that Tehran will back the Syrian government and army. Arab leaders, including Jordan’s King Abdullah II and United Arab Emirates President Sheikh Mohammed bin Zayed Al Nahyan, in calls with Assad expressed their solidarity with Damascus.

Turkey, a main backer of Syrian opposition groups, said its diplomatic efforts had failed to stop Syrian government attacks on opposition-held areas in recent weeks. Turkish security officials said a limited offensive by the rebels was planned to stop government attacks and allow civilians to return, but the offensive expanded as Syrian government forces began to retreat from their positions.

The insurgency, led by Salafi jihadi group Hayat Tahrir al-Sham and which includes Turkey-backed fighters, launched their offensive on Wednesday with a two-pronged attack on Aleppo and the Idlib countryside, before moving toward Hama province. In Aleppo province, they captured a strategic town that lies on the highway linking Aleppo with Damascus and the coast.

Rebel commander Col. Hassan Abdulghani said that despite the government counteroffensive, his fighters were making gains in Aleppo. He says they took control of Sheikh Najjar, also known as the Aleppo Industrial City, Aleppo’s military academy and the field artillery college.

Abdulghani said 65 Syrian troops were taken prisoner in eastern Aleppo.

Elsewhere, he said the insurgents advanced in the Idlib countryside, putting all of the province under their control.

The United Nations special envoy for Syria said the shock push by the rebels poses a risk to regional security and called on resuming diplomatic efforts to end the conflict.

“I have repeatedly warned of the risks of escalation in Syria, of the dangers of mere conflict management rather than conflict resolution,” Geir Pedersen said in a statement. He said the reality is that no Syrian party or grouping of actors can resolve the conflict via military means.

Syrian Troops Fortify Northern Hama as Jets Pound Idlib
According to Syrian state news agency SANA and a war monitor, the army overnight pushed back insurgents in the northern countryside of Hama province.

Syrian state media said government resupply included heavy equipment and rocket launchers while Syrian and Russian airstrikes targeted weapon depots and insurgent strongholds.

Britain-based opposition war monitor the Syrian Observatory for Human Rights said that government reinforcements created a “strong defensive line” in the northern Hama countryside. Syrian state television claimed government forces had killed nearly 1,000 insurgents over the past three days, without providing evidence or details.

Government airstrikes in Idlib on Sunday killed at least three civilians, including two children, and wounded 11 others, said the Syrian Civil Defense, known as the White Helmets, which operates in opposition-held areas. Among the targets was the Aleppo Hospital University in the city center, though there was no word of casualties.

The insurgents vowed to push all the way into Damascus, but life in the Syrian capital remained normal with no signs of panic.

In his first public comments since the start of the offensive, released by the state news agency Saturday evening, Assad said Syria will continue to “defend its stability and territorial integrity against terrorists and their supporters.” He added that Syria is able to defeat them no matter how much their attacks intensify.

The 2016 battle for Aleppo was a turning point in the war between Syrian government forces and rebel fighters after 2011 protests against Assad’s rule turned into an all-out war. After appearing to be losing control of the country to the rebels, the Aleppo battle secured Assad’s hold on strategic areas of Syria, with opposition factions and their foreign backers controlling areas on the periphery.