A tragic car bomb explosion in northern Syria has claimed the lives of at least 15 agricultural workers, according to reports from the country’s civil defense force. The blast occurred on Monday in the city of Manbij, a hotspot for clashes between armed groups, and is among the deadliest attacks since the fall of Bashar al-Assad in December.

The explosion happened as the workers were being transported in the back of a truck on the outskirts of Manbij, a city located about 20 miles from the Turkish border. Footage from the scene showed the devastating aftermath, with the truck riddled with shrapnel and a nearby vehicle completely mangled. Most of the victims were women, and at least 15 others were injured, with fears that the death toll could rise.

No group has yet claimed responsibility for the attack, but the region has seen a surge in violence since Turkish-backed fighters took control of Manbij from Kurdish-led forces last December. Both groups have ties to foreign powers, with the U.S. supporting the Kurdish forces and Turkey backing their rivals.

This latest incident highlights the immense challenges facing Syria’s interim president, Ahmed al-Shara, who was appointed last week. Al-Shara has vowed to create a unified government and dissolve all armed factions, but resistance remains strong, particularly from Kurdish-led forces in the northeast.

Experts warn that bringing together Syria’s fragmented armed groups is a daunting task, one that will be critical to achieving any semblance of stability in the war-torn nation. As violence continues to plague the region, the road ahead appears long and uncertain.