U.S. confirms American soldiers, civilians among 19 killed in Syria suicide bombing

A bomb attack claimed by Islamic State killed two U.S. soldiers and two civilians working for the U.S. military in northern Syria on Wednesday, weeks after U.S. President Donald Trump said the group had been defeated there and that he would pull out all American forces.

ISIS claims attack that occurs weeks after Trump said group was defeated in region

This frame grab from video provided by Hawar News, ANHA, the news agency for the semi-autonomous Kurdish areas in Syria, shows a damaged restaurant where an explosion occurred in Manbij on Wednesday. (ANHA via The Associated Press)

A bomb attack claimed by Islamic State killed two U.S. soldiers and two civilians working for the U.S. military in northern Syria on Wednesday, weeks after U.S. 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 U.S. forces in Syria since they deployed on the ground there in 2015. The town is controlled by a militia allied to U.S.-backed Kurdish forces.

The U.S. military confirmed the four Americans were killed and said three U.S. troops were also wounded in the explosion, which an Islamic State-affiliated website said was the work of a suicide bomber.

The Syrian Observatory for Human Rights monitoring group said 19 people had been killed in all, including four Americans.

It was unclear what impact the blast might have on Trump's plans after he confounded his own national security team with a surprise decision last month to withdraw all 2,000 U.S. troops from Syria, declaring Islamic State had been defeated there.

No experts believe ISIS (Islamic State in Iraq and Syria) 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 Dec. 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 U.S.-backed Kurdish forces in northern Syria.

U.S. reaffirms plan to leave Syria

Hours after the blast, U.S. Vice-President Mike Pence said he and Trump condemned the attack. He simultaneously restated U.S. 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 U.S. pullout.

"As we begin to bring our troops home, the American people can be assured, for the sake of our soldiers, their families, and our nation, we will never allow the remnants of ISIS to reestablish their evil and murderous caliphate," Pence said.

Turkish President Tayyip Erdogan said he did not believe the attack would have an impact on the U.S. decision to withdraw from Syria, "because I saw honourable Trump's determination on this point."

How, and how quickly, U.S. 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 U.S.-backed Kurdish fighters for the 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 U.S. personnel were meeting members of the militia backed by Washington. The U.S. military's Central Command said in a statement that the attack happened "while conducting a local engagement in Manbij."

An ISIS statement later said a Syrian fighter had detonated his explosive vest on a foreign patrol in Manbij.

Two witnesses described the blast to Reuters.

U.S. armoured vehicles are seen at the scene of a suicide attack in the northern Syrian town of Manbij on Wednesday. (AFP/Getty Images)

"An explosion hit near a restaurant, targeting the Americans, and there were some forces from the Manbij Military Council with them," one said.

The council militia has controlled the town since U.S.-backed Kurdish-led forces took it from Islamic State in 2016. Manbij is near areas held by Russian-backed Syrian government forces and by anti-Assad fighters backed by Turkey.

The council said in a statement that women and children were among civilians killed and offered condolences for the "hero American soldiers" who died.

One of the witnesses said there was a "heavy" presence of military aircraft over Manbij following the blast.

At the Pentagon, acting U.S. Defence Secretary Patrick Shanahan offered his condolences to the families.

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.