A missile fired by fighters from the Islamic State militant group (ISIS) wounded two British soldiers and killed an allied Kurdish fighter on Saturday, an NGO said.
Their injuries were confirmed by the Syrian Observatory for Human Rights, a UK-based monitor with a wide network of sources in the war-torn country. It said that the two soldiers were part of the anti-ISIS coalition operating in Syria and led by the United States.
"The two British soldiers were transported by helicopter to receive medical care," the observatory's director Rami Abdulrahman said.
The attack took place in the village of Al Shaafa in Deir Ezzor Province, located in eastern Syria and representing one of the last slithers of territory that the militant group controls in the Euphrates River valley.
ISIS once controlled large areas of territory across Iraq and Syria but has seen its territorial foothold fall significantly in the last two years. One of its last major strongholds, the town of Hajin in eastern Syria, fell in December.
Since September, more than 1,000 extremists have been killed in the fighting compared with just under 600 SDF members while 15,000 people have fled Hajin, according to the Observatory.
The Syrian Democratic Forces, a coalition of Kurdish and Arab fighters that has largely fought the ground operations against ISIS in Syria, is increasing concerned about their future after US President Donald Trump’s abrupt decision to remove American troops from Syria last month.
The US has around 2,000 soldiers in Syria but Mr Trump argued that ISIS had been defeated in the country.
The speed of that withdrawal appears to have changed as key presidential aides have warned him about the risks of leaving a vacuum that could be filled by ISIS or regional foe Iran.
The Kurds in northern Syria fear a renewed offensive by Turkey, which has promised to prevent their territorial control on its southern border for security reasons.