Two extremist commanders close to al-Qaeda were killed in Monday (September 20) drone strikes in northwest Syria's Idlib province, the Syrian Observatory for Human Rights said.
The US military acknowledged killing an al-Qaeda official.
"US forces conducted a kinetic counter-terrorism strike near Idlib, Syria, today, on a senior al-Qaeda leader," US Central Command (CENTCOM) spokeswoman Lt. Josie Lynne Lenny said in a statement.
"Initial indications are that we struck the individual we were aiming for, and there are no indications of civilian casualties as a result of the strike," she said.
It was the first recorded US strike in northwest Syria since early 2021.
The strikes targeted a vehicle on the road leading northward from Idlib city to Binnish, in Idlib province, according to the Observatory.
Observatory chief Rami Abdel Rahman said one of the commanders killed was Tunisian, while the other was from Yemen or Saudi Arabia, without identifying the group they belonged to.
Reports circulating on news sites and social media said two Hurras al-Deen officials had been killed: Abu al-Bara al-Tunsi, who is a senior religious figure, and Abu Hamza al-Yemeni.
Hurras al-Deen is a relatively small but powerful armed group led by al-Qaeda loyalists. In June 2020, it joined forces with four other hardline groups operating in the region to form the Fathbatu operations room.
Considered to be al-Qaeda's branch in Syria, Hurras al-Deen is a rival of Tahrir al-Sham, an extremist alliance dominated by former members of al-Qaeda linked al-Nusra Front (ANF) -- although the two groups co-operate at times.
The United States has carried out attacks in Idlib before, targeting al-Qaeda and affiliated groups. It also killed "Islamic State of Iraq and Syria" (ISIS) leader Abu Bakr al-Baghdadi, in an October 2019 raid on his hideout in the province.
In October, another US drone strike targeted a car in which three members of Hurras al-Deen were traveling in northwest Syria, killing everyone on board.