A pair of US F-15 fighter jets struck an Iran-supported weapons storage facility in north-eastern Syria, the Pentagon said late on Wednesday, in what it described as a “self-defence” action that follows near-daily attacks on US and coalition personnel stationed in the Middle East.
The Pentagon said the facility destroyed in the strike in Maysulun in Deir Ezzor province was being used by Iran's Islamic Revolutionary Guard Corps.
The strike resulted in secondary explosions from whatever was being stored inside, a senior military official said.
This is the second such strike carried out by the US since the Israel-Gaza war began.
Iranian proxies have conducted several attacks on US and coalition forces in Iraq and Syria since shortly after Hamas launched attacks on Israel on October 7.
The US, which is trying to contain the Israel-Gaza war, has been reluctant to draw a connection between Israel's military assault on the Gaza Strip and the increased hostilities from Iran-backed groups.
But since mid-October, there have been more than 40 attacks in Iraq and Syria on American and coalition forces.
“There has been an increase in Iran and Iran-backed attacks against US forces since October 17, which is why you've seen us use precise, deliberate and targeted self-defence force to make it clear that we will not tolerate it, we will respond and we want Iran's leaders to stop,” a senior defence official told reporters.
Secretary of Defence Lloyd Austin confirmed in a statement that the strike was ordered by President Joe Biden.
The Pentagon said Russia, which has operated in Syria since 2015, was notified of the strike through a deconfliction channel.
On October 27, US fighter jets conducted precision strikes on two Syria munitions sites also used by the IRGC and other groups it supports.
Separately on Wednesday, a US drone was shot down over the Red Sea by Iranian-backed Houthi rebels in Yemen, the Pentagon confirmed, further complicating the American presence in the Middle East.
Two US officials earlier confirmed to AP that a drone had been brought down but agencies were analysing whether it was shot down over Yemeni airspace or international waters.
The Houthis in Yemen have carried out a number of attacks against Israel after its bombardment of Gaza began, but Wednesday's drone strike was the Houthis' first against a US asset since October 7.
Mr Biden in October warned Iran against widening the conflict in the region, advising Iranians to “be careful”.
Mr Austin said the US would take other measures if needed in the future.
“The United States is fully prepared to take further necessary measures to protect our people and our facilities,” he said.
“We urge against any escalation.”