BEIRUT — An air raid struck several cars in northwestern Syria, killing at least eight people, including Al Qaeda-linked fighters and a senior commander with a Chinese Islamic militant faction, an activist group and a local jihadi commander said Monday.

The attack occurred late Sunday on a road leading from the town of Sarmada to the Bab al-Hawa area on the border with Turkey, said the Britain-based Syrian Observatory for Human Rights and a local commander with the Fatah al-Sham Front, an Al Qaeda-linked group.

The Observatory’s chief, Rami Abdurrahman, said the attack is widely believed to have been carried out by the US-led coalition.

The United States has killed some of Al Qaeda’s most senior commanders in Syria over the past two years in airstrikes. Those targeted included members of the so-called Khorasan group, which Washington describes as an internal branch of Al Qaeda that plans attacks against Western interests.

The Observatory said three jihadi commanders were among the victims. The dead include a senior Al Qaeda commander known as Khattab al-Qahtani, who was from the Gulf region and fought for the group in Afghanistan.

Abu Omar al-Turkistani, a commander with the Turkistan Islamic Party, and a Syrian Al Qaeda commander known as Abu Muatasem al-Deiri were also killed. The Turkistan Islamic Party mainly consists of minority Uighurs from China, many of whom have traveled to Syria to help battle President Bashar Assad’s forces alongside other jihadi groups.

The report came as a cease-fire held for the fourth day amid sporadic violations.