AMMAN: The capture of key regions of Idlib province by a hardline Islamist faction is raising fresh questions about the future of necessary humanitarian aid in northwestern Syria, despite the rebel coalition’s assurances that border crossings and the capital will be handed over to civilian administration.

Rebel coalition Hay’at Tahrir a-Sham (HTS)—led by former Al-Qaeda affiliate Jabhat Fatah a-Sham—seized the provincial capital of Idlib city from the rival faction Ahrar a-Sham on Sunday.

The capture of Idlib city—control of which had been divided between the two rival factions—followed five days of bloody battles in the latest violent outbreak of rebel infighting that has engulfed Syria's opposition-held northwest.

After weeks of military mobilizations and failed attempts at mediation, clashes erupted between the two rival factions across the province last week after a reported dispute over Ahrar a-Sham’s use of the Syrian revolutionary flag, Syria Direct reported at the time.

A car bomb detonated in Idlib city shortly after HTS took over on Sunday, killing 12 people and injuring more than a dozen more, the pro-opposition Edlib Media Center reported. No party claimed credit for the blast.

The inter-rebel clashes over the past week have prompted the closure of the two border points—Bab al-Hawa and the Khirbet al-Jouz humanitarian crossing—on Idlib province’s border with Turkey, two administrators told Syria Direct on Monday.

On Sunday, HTS seized the Syrian border town of Khirbet al-Jouz from Ahrar a-Sham, the entry point for humanitarian aid and the site of three medical facilities that treated displaced families and local residents. Three days before, HTS seized control of the Bab al-Hawa border crossing, 60km north of Idlib city, a key gateway for humanitarian aid entering the province from Turkey.

“The crossings were a lifeline for northern Syria,” Abu Luai, an administrator at the Khirbet al-Jouz crossing, told Syria Direct on Monday, asking not to be identified by his real name. “We don’t know what will happen to them.”

After a car bomb detonated in Idlib city on Sunday. Photo courtesy of the Idlib News Network.

In addition to Khirbet al-Jouz and Bab al-Hawa, Turkish authorities have also closed the Yamadiyah border crossing in rebel-held northern Latakia province near the border with Idlib in response to the infighting, said Abu Luai.

Turkish-based humanitarian organizations use the three crossings to deliver bread, flour and medical supplies to displaced residents in Idlib province.

Idlib, the only province fully controlled by opposition forces, is home to tens of thousands of displaced residents who have evacuated their cities and towns over the past year because of surrender agreements with the regime.

For IHH, an Istanbul-based humanitarian organization, the border crossing closures mean that aid deliveries to residents in Idlib province are temporarily suspended.

“IHH bread and flour deliveries stopped several days ago because of the clashes happening between factions,” Jalal Damir, a regional director for IHH in Turkey’s southern Gaziantep province, told Syria Direct on Monday.

Continued closure of the border crossings “means a slow death for the opposition territories,” Saeed, the pseudonym of an administrator at the Bab al-Hawa crossing, told Syria Direct on Monday.

Turkish border authorities will reopen open Bab al-Hawa if it is “handed over to civilian administration,” Saeed added.

Hay’at Tahrir a-Sham and Ahrar a-Sham agreed to hand over control of the border crossing to civilian administrators on Friday, Ahrar a-Sham announced in a statement that day.

The agreement called for “a ceasefire, the release of detainees on both sides, and the evacuation of [all] factions from the Bab al-Hawa crossing, which will be handed over to a civilian administration,” according to an Ahrar statement on the ceasefire published by their media outlet the same day.

However, the agreement quickly unraveled over the weekend with clashes centered in the provincial capital Idlib city.

On Sunday night, Hay’at Tahrir a-Sham and Ahrar a-Sham announced that the two groups agreed to reinstate Friday’s agreement through a statement that circulated on social media.

Sunday’s updated treaty also called for the end of arrests and military mobilization, as well as the resolution of all inter-rebel disputes within a period of five days.

Despite HTS claims that civilians will take over control of the crossings, an HTS spokesman told Syria Direct on Monday that he could not provide any details on when the handover will occur.

“I do not have a timeline for implementation,” Emad a-Din Mujahid told Syria Direct on Monday.

As for Ahrar a-Sham, the rebel alliance remains wary of rival HTS’s intentions and the viability of the ceasefire agreement.

“We are ready to respond if they [HTS] don’t adhere to the most recent agreement,” Abu Mohammed, an Ahrar a-Sham commander, told Syria Direct on Monday. "They are liars."

Several sources in the province told Syria Direct that there were no clashes between Ahrar a-Sham and Tahrir a-Sham fighters in the capital or the northern countryside on Monday.

“The city is calm today, but people are afraid of the coming days,” Sharif al-Khatib, a resident of Idlib’s provincial capital, told Syria Direct on Monday.

"People are so tired of these factions."