It is the second time in roughly two weeks that the United States has targeted a location in Syria it said was linked to Iran, which supports an array of groups that Washington blames for a spike in attacks on its forces in the Middle East.

The United States is striving to deter Iran and its proxies from turning the Israel-Hamas fighting into a regional war, but the repeated attacks and strikes in response risk a conflict between Washington and Tehran.

"US military forces conducted a self-defense strike on a facility in eastern Syria used by Iran's Islamic Revolutionary Guard Corps (IRGC) and affiliated groups. This strike was conducted by two US F-15s against a weapons storage facility," Austin said in a statement.

"This precision self-defense strike is a response to a series of attacks against US personnel in Iraq and Syria by IRGC-Quds Force affiliates," Austin said, adding that the United States "is fully prepared to take further necessary measures to protect our people and our facilities."

The surge in attacks on US troops is linked to the war between Israel and Hamas, which began when the militant group carried out a shock cross-border attack from Gaza on October 7 that Israeli officials say killed more than 1,400 people.

Israel's military responded with a relentless air, land and naval assault on Gaza that the territory's health ministry said Monday has left more than 10,500 people dead.

There are roughly 2,500 American troops in Iraq and some 900 in Syria as part of efforts to prevent a resurgence of the Islamic State.

The jihadist group once held significant territory in both countries but was pushed back by local ground forces backed by international air strikes in a bloody multi-year conflict.