Two US soldiers and a US civilian interpreter have been killed in Syria in an ambush by an Islamic State (IS) gunman, the US Central Command (Centcom) has said.

Officials said three other service members were injured in the attack, during which the gunman was 'engaged and killed'. Syria's state news said two Syrian service personnel were also injured.

US President Donald Trump wrote on social media that it was 'an ISIS attack' against the US and Syria and said there would be 'a very serious retaliation'. The Syrian government has issued a statement condemning the attack.

The identities of those killed are being withheld for 24 hours until their next of kin have been informed, Centcom said.

In a post on X, Centcom noted that the ambush was carried out by a lone ISIS gunman, while a Pentagon official indicated it was 'likely' linked to the Islamic State group.

The attack occurred in Palmyra, while the soldiers were 'conducting a key leader engagement', according to Pentagon spokesperson Sean Parnell.

US Defence Secretary Pete Hegseth condemned the attack, warning that those who target Americans 'will ruthlessly be hunted down'.

Syria's Foreign Minister Asaad al-Shaibani condemned the attack and offered condolences to the victims' families. The incident underscores the ongoing partnership between US and Syrian forces against IS, even amidst recent dialogues aimed at fostering a supportive coalition.

Despite prior claims that IS had lost its territorial stronghold in Iraq and Syria, estimates suggest that the group still possesses thousands of fighters capable of conducting attacks in the region.