DAMASCUS, Syria — A car bomb exploded on the outskirts of a northern Syrian city on Monday, killing at least 19 people, all but one of them women, and leaving more than a dozen wounded, hospital workers said.

The car detonated next to a vehicle carrying mostly female agricultural workers on the outskirts of the city of Manbij.

The dead included 18 women and one man, a nurse at the hospital, Mohammad Ahmad, told The Associated Press. Another 15 women were wounded, some of them in critical condition, according to the local Syrian civil defense.

No group immediately claimed responsibility for the explosion.

Seventh Car Bomb Explosion in a Month

It was the seventh car bomb explosion in Manbij in just over a month, said Munir Mustafa, the deputy director of civil defense.

Manbij in northeastern Aleppo province continues to witness violence even after the downfall of President Bashar Assad in December.

Turkish-backed factions, known as the Syrian National Army, have clashed with the U.S.-backed Kurdish-led Syrian Democratic Forces. The factions took the city from the SDF in early December during the lightning insurgency that toppled Assad.

Not long after accusations against the SDF surfaced on Syrian social media accounts, the SDF in a statement condemned the attack and accused Ankara-backed groups of possibly being involved in order to cause more internal strife in the country. The statement said they will communicate with Syria’s new interim government in Damascus to investigate the circumstances surrounding the attack.

Constant Attacks Keep Residents on Their Toes

A resident said the car that detonated was parked on the roadside. The recurring attacks have forced residents to become more vigilant, he said.

“There are efforts from the people of Manbij to focus on protecting some neighborhoods as well as setting up surveillance cameras in the main neighborhoods of the city,” Jameel al-Sayyed, a Manbij activist and journalist said.

Mustafa warned that the attacks in Aleppo province near Syria’s second city are a threat to Syria’s progress to bring about post-war security and economic recovery. Most of the explosions took place at night.

“The continued attacks on Syrian civilian areas and targeting civilians while they are trying to recover from the effects of the war of the defunct Assad regime … threaten their lives, deepens their humanitarian tragedy, undermines educational and agricultural activities and livelihoods, and worsens the humanitarian situation in Syria,” Mustafa said.

A car bombing in Manbij on Saturday killed four civilians and wounded nine, state news agency SANA reported, citing civil defense officials.