A bomb attack claimed by Islamic State has killed two US troops and two civilians working for the US military in northern Syria, weeks after President Donald Trump said the group had been defeated there and that he would pull out all American forces.
The attack in Manbij appeared to be the deadliest on US forces in Syria since they deployed on the ground there in 2015. The town is controlled by a militia allied to US-backed Kurdish forces.
The US military confirmed four Americans were killed and said three US troops were wounded in the explosion, which an Islamic State-affiliated site said was the work of a suicide bomber.
The Syrian Observatory for Human Rights monitoring group said 19 people had been killed in all.
It was unclear what impact the blast might have on Trump's calculus after he confounded his own national security team with a surprise decision last month to withdraw all 2,000 US troops from Syria, declaring Islamic State had been defeated there.
No experts believe Islamic State has been defeated, despite the group having lost almost all of the territory it held in 2014 and 2015 after seizing parts of Syria and Iraq and declaring a "caliphate."
Trump's December 19 announcement was one of the reasons his defence secretary, Jim Mattis, resigned. It stunned allies and raised fears of a long-threatened Turkish military offensive against US-backed Kurdish forces in northern Syria.
Hours after the blast, US Vice President Mike Pence said he and Trump condemned the attack. He simultaneously restated US plans to withdraw while also saying Washington would never allow Islamic State to re-establish itself - something experts say it will try to do following a US pullout.
How, and how quickly, US forces leave has caused ructions in northern Syria, with both Turkey and the Syrian government of President Bashar al-Assad ready to fill the vacuum.
The US-backed YPG militia that is allied to the fighters holding Manbij last month invited Assad into the area around the town to forestall a potential Turkish assault. Syrian army troops entered the area soon after.
A witness in Manbij said Wednesday's attack had targeted a restaurant where US personnel were meeting members of the militia backed by Washington. The US military's Central Command said in a statement that the attack happened "while conducting a local engagement in Manbij."
Syria's civil war has killed half a million people, forced more than half the country's pre-war population from their homes and dragged in global and regional powers. Assad controls most of the country.
Australian Associated Press