US troops attacked in Syria, Iraq as anger mounts over Israel support

US troops have been repeatedly attacked in Iraq and Syria in recent days, US officials said, as Washington remains on heightened alert amid soaring tensions due to Israel's war on besieged Gaza.

"While I'm not going to forecast any potential responses to these attacks, I will say that we will take all necessary actions to defend US and coalition forces against any threat," Pentagon spokesperson Brigadier General Patrick Ryder told reporters on Thursday.

"Any response, should one occur, will come at a time in a manner of our choosing," Ryder said.

President Joe Biden has sent naval power to the Middle East in the past two weeks, including two aircraft carriers, other warships and about 2,000 Marines.

On Wednesday, a drone hit US forces in Syria, resulting in minor injuries, while another one was brought down.

During a false alarm at Al Asad airbase in Iraq, a civilian contractor died from a cardiac arrest.

Earlier this week, US forces thwarted multiple drones targeting troops in Iraq.

On Thursday, drones and rockets targeted the Ain al Asad air base, which hosts US and other international forces in western Iraq, and multiple blasts were heard inside the base.

A US Navy warship travelling near Yemen on Thursday intercepted missiles and several drones that were launched by what Ryder said was the Houthi movement, though it appeared that the projectiles were potentially heading in the direction of Israel.

Link to Israel war on Gaza?

Israel has called up a record 360,000 reservists and has been relentlessly bombarding the Palestinian enclave of besieged Gaza.

At least 3,785 Palestinians have been killed and 12,493 wounded in Israeli strikes on Gaza, the Health Ministry in Gaza said. But Ryder said he did not see a link between the rise in attacks and Israel's war on Gaza.

"At this point, again, the information that we have does not show a direct connection to the Hamas attacks on October 7," he said.

The United States has 2,500 troops in Iraq, and 900 more in neighbouring Syria.

In Iraq, tension over the war in Gaza had already been high.

Its top Shia Muslim cleric, Grand Ayatollah Ali al Sistani, last week condemned Israel and called on the world to stand up to the "terrible brutality" in blockaded Gaza.

Kataib Hezbollah, a powerful armed faction with close ties to Iran, accused the United States of supporting Israel in "killing innocent people" and said it should leave Iraq.