The US-led coalition against the jihadist group Islamic State (IS) says it has killed up to 150 militants in air strikes on a headquarters in Syria.
A statement said the strikes took place on Saturday near al-Shafah, in the Middle Euphrates river valley in the south-eastern province of Deir al-Zour.
A combination of intelligence and continuous target observation ensured no civilians were harmed, it added.
There was no confirmation of the attack from IS or its supporters.
However, the group's Amaq news agency did say 14 people, including seven women, were killed in US air strikes that targeted al-Shafah on Tuesday.
The activist-run Deirezzor24 website also said the village was hit that day.
The coalition says the group has lost 98% of the territory that it seized across Iraq and Syria in 2014, when it proclaimed the creation of a "caliphate".
IS now controls only small pockets of land in Syria, including a part of the Euphrates valley, where it is under attack by a US-backed alliance of Kurdish and Arab fighters called the Syrian Democratic Forces (SDF), as well as Syrian pro-government forces supported by Russia and Iran.
The coalition statement said the "precision strikes" on the IS headquarters and command-and-control centre near al-Shafah came after an extensive intelligence operation that included SDF fighters assisting in target observation.
"The combination of intelligence and continuous eyes on the target ensured no accidental engagement of non-military personnel," it added.
Militants were "massing for movement" at the headquarters before it was hit, according to the coalition, which said between 145 and 150 were killed.
"The strikes underscore our assertion that the fight to liberate Syria is far from over," said Maj Gen James Jarrard, commander of special operations for the coalition.
"Our SDF partners are still making daily progress and sacrifices, and together we are still finding, targeting and killing [IS] terrorists intent on keeping their extremist hold on the region."
The comments from the general came as Turkish forces and allied Syrian rebels continued an offensive against the Kurdish militia that dominates the SDF - the People's Protection Units (YPG) - in the north-western border region of Afrin.
Turkey says the militia is an extension of the banned Kurdistan Workers' Party (PKK), which has been fighting for Kurdish autonomy in Turkey for decades. The YPG denies any direct organisational links with the PKK.