Two U.S. service members and a civilian American interpreter were killed Saturday in Syria after an apparent ambush by an ISIS-affiliated gunman, U.S. officials said.

The attack occurred in Palmyra, Syria, as the U.S. troops were conducting a key leader engagement in support of ongoing counter-ISIS and counterterrorism operations, according to Pentagon spokesperson Sean Parnell.

The suspected gunman was killed during a subsequent skirmish by partner forces, Defense Secretary Pete Hegseth said.

Three additional U.S. service members were wounded in the incident. Two U.S. officials confirmed to  News men  that the injured personnel were Americans.

“This attack occurred as the soldiers were conducting a key leader engagement,” Parnell said in a statement. “Their mission was in support of ongoing counter-ISIS operations in the region.”

The deaths mark the first U.S. combat fatalities since President Donald Trump returned to office.

President Trump expressed condolences on social media Saturday and vowed retaliation, calling the incident an ISIS attack targeting both U.S. and Syrian interests. He said Syrian President Ahmed al-Sharaa was “extremely angry and disturbed” by the assault and warned of a strong response.

Trump later echoed those remarks briefly to reporters, saying, “We will retaliate,” before leaving without taking questions.

The identities of the fallen soldiers have not yet been released as next-of-kin notifications are ongoing, officials said.