On Thursday, following media reports that the US had carried out an airstrike against “Iran-backed” assets on Syrian territory, the US Department of Defense confirmed the information, saying that airstrikes were conducted in response to recent attacks in Iraq.

According to the DoD statement, multiple facilities that had been used by these terrorist groups, such as Kata’ib Hezbollah and Kata’ib Sayyid al-Shuhada, were destroyed.

“At President Biden’s direction, US military forces earlier this evening conducted airstrikes against groups in eastern Syria. These strikes were authorized in response to recent attacks against American and Coalition personnel in Iraq, and to ongoing threats to those personnel”, the statement read.

The Pentagon highlighted that the attack, described as a “proportionate military response”, was conducted “together with diplomatic measures, including consultation with Coalition partners”.

The UK-based Syrian Observatory for Human Rights said on Friday that at least 17 pro-Iran fighters were killed in the airstrikes.

“The strikes destroyed three lorries carrying munitions, and there were many casualties. Preliminary indications are that at least 17 fighters were killed, all members of Popular Mobilisation Forces,” the director of the SOHR, Rami Abdul Rahman, told AFP.

The airstrike followed a series of missile attacks against US assets in Iraq that occurred earlier in February. Iraqi officials asserted that Iran stood behind the attacks – a claim that Iran has rejected.