The United States Central Command (CENTCOM) said Saturday that two US service members and a civilian were killed by a lone gunman affiliated with the so-called "Islamic State" in central Syria. 

What do we know so far? 

In post on X, CENTCOM said the ambush also left three other service members wounded. "The gunman was engaged and killed," CENTCOM added. 

A component of the US Defense Department, CENTCOM is in charge of defending and promoting American interests in the Middle East and Central and South Asia.

Chief Pentagon Spokesman Sean Parnell said the soldiers in Palmyra were conducting a "key leader engagement" in support of anti-IS and counterterrorism operations in the region. 

"The soldiers' names, as well as identifying information about their units, are being withheld until 24 hours after the next of kin notification," Parnell said, while adding that an investigation is underway.    

US Secretary of Defense Pete Hegseth, who is also known as the Secretary of War, called the attacker a "savage" on X.

"Let it be known, if you target Americans — anywhere in the world — you will spend the rest of your brief, anxious life knowing the United States will hunt you, find you, and ruthlessly kill you," Hegseth said.     

US Ambassador to Turkey and Special Envoy for Syria Tom Barrack said he strongly condemns the "cowardly terrorist ambush targeting a joint US-Syrian government patrol in central Syria."

Trump vows 'very serious retaliation' 

In  a post on his Truth Social platform, US President Donald Trump said, "we mourn the loss of three Great American Patriots in Syria." 

Trump said the area where the attack occurred was "very dangerous" and added that Syrian President Ahmad Sharaa is "extremely angry and disturbed by this attack."

"There will be very serious retaliation," Trump added.

IS attacker was member of security forces, Syrian government says 

The Syrian Interior Ministry said there were "prior warnings from the internal security command" to allied troops operating in the desert areas of central Syria.    

"The international coalition forces did not take the Syrian warnings of a possible IS infiltration into consideration," Syrian Interior Ministry spokesperson Anwar al-Baba said on Syrian state television.    

The Syrian Interior Ministry also said that the attacker was a member of the Syrian security forces and held "extremist ideology." 

First deadly IS incident involving US forces in post-Assad Syria 

The shooting is the first deadly incident against US forces in Syria since rebels ousted President Bashar Assad last year. 

Assad, who maintained close ties with Russia and Iran, fought back an uprising from rebels in 2011, which then ignited a civil war that lasted more than a decade.

As the war raged, IS took control of the major Syrian city of Raqqa in 2014 and also seized the major metropolis of Mosul in neighboring Iraq that same year.

IS had later lost control of almost all of its territory in 2019 after a series of airstrikes from the US, France, Jordan and several other countries. The US-backed and Kurdish-led Syrian Democratic Forces were crucial in driving IS out of Syria.  

Since Assad's ouster, the new Syrian administration under Sharaa has sought closer ties with the US particularly in the area of counterterrorism, with Syria joining the US-led Global Coalition to Defeat ISIS in November. 

Reuters and other outlets also reported in November that Syria foiled two IS plots to assassinate Sharaa.  

Edited by: Karl Sexton