U.S. troops were attacked again over the weekend across the Middle East amid Pentagon fears that Iranian-backed groups may seek to undermine the American presence alongside the Israel-Hamas war.

The number of attacks has now risen to 38, according to the Defense Department, including 20 in Iraq and 18 in Syria. That’s up from 32 at the end of last week.

Iranian-backed militant groups have launched drone and rocket attacks at U.S. bases, injuring several people but not killing anyone.

Pentagon press secretary Brig. Gen. Pat Ryder told reporters the attacks are “harassing” troops while resulting in 45 injuries of varying degrees.

That includes at least 24 service members with traumatic brain injuries and the rest with minor injuries, such as shrapnel wounds, rolled ankles or headaches.

The rise in the overall number shows U.S. forces were attacked six times over the weekend, indicating militant groups are not backing down.

Washington has deployed hundreds of troops, two aircraft carriers and a nuclear-powered submarine to the Middle East to deter any groups from taking advantage of the unrest in the region sparked by Israel’s war with Palestinian militant group Hamas.

The Biden administration has increasingly warned Iran and other potential aggressors from escalating tensions. Secretary of State Antony Blinken reiterated those calls during a surprise visit to Iraq on Sunday.

Ryder on Monday said the U.S. is trying to “make sure that this does not spiral into escalation” and would continue to protect American troops in the region.

“We will make sure that we’re taking any necessary actions to protect our forces,” Ryder said.