The Trump administration announced Monday it is sending an additional 1,000 American troops to the Middle East after it accused Iran of orchestrating attacks on two tankers in the Gulf of Oman last week. The Defense Department said the troops would be deployed for “defensive purposes” and, NPR reports, would be primarily comprised of intelligence, reconnaissance and surveillance (ISR), as well as force protection and engineers. The increase in troop levels is part of a more general, though still modest buildup that began last month after another series of attacks on ships in the region that the U.S. similarly suspects is Iran’s doing.

The U.S., it’s worth noting, is still without a confirmed Secretary of Defense as relations in the region are increasingly strained. “In response to a request from the US Central Command for additional forces, and with the advice of the Chairman of the Joint Chiefs of Staff and in consultation with the White House, I have authorized approximately 1,000 additional troops for defensive purposes to address air, naval, and ground-based threats in the Middle East,” acting Defense Secretary Patrick Shanahan said in a statement. “The recent Iranian attacks validate the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups that threaten United States personnel and interests across the region.”