The US military confirmed that two US service members and two other Americans were killed in Syria on Wednesday in an explosion that raises questions about Trump administration claims that ISIS has been defeated.

It was the deadliest day in Syria for US forces since they entered the country in 2015. Prior to Wednesday, two US troops had died in combat there.

US Central Command confirmed the deaths in a statement that provided few other details.

“Two U.S. servicemembers, one Department of Defense (DoD) civilian and one contractor supporting DoD were killed and three servicemembers were injured while conducting a local engagement in Manbij, Syria, Jan. 16, 2019,” the statement said. “Initial reports indicate an explosion caused the casualties, and the incident is under investigation.”



ISIS claimed responsibility for the attack, saying it was carried out by a suicide bomber. The US did not assign responsibility, but the group that has been the primary US ally in Syria against ISIS said the explosion shows ISIS has not been defeated.



“This shows that ISIS has not yet finished,” said Aldar Khalil, a political official aligned with the Syrian Democratic Forces. “The territory that was governed by ISIS has shrunk, but they exist as sleeper cells.”

The Syrian Observatory for Human Rights, a group that monitors the Syrian conflict, reported that the attack took place outside a restaurant and killed two members of the “international coalition” as well as five “local fighters” who’d been escorting the foreign troops. It said nine civilians also died.



The attack came less than a month after President Trump ordered US troops to withdraw from Syria, claiming that ISIS had been defeated there. Vice President Mike Pence repeated that claim Monday at the State Department in an address in which he said nothing about the US deaths.

“The caliphate has crumbled and ISIS has been defeated,” Pence said.

Later, his office released a statement in which he condemned the attack, but insisted that “we have crushed the ISIS caliphate and devastated its capabilities.”