Iran attacked American forces in the Middle East overnight, prompting Saudi Arabia and the United States to retaliate against a Tehran-backed militia in Iraq and shattering a period of relative calm raising the risk of a further escalation of the conflict.

Iran had suspended its attacks amid a renewed push to reach a deal with the U.S., but warned earlier this week that it would not allow the U.S. to dictate the “timing of war and peace,” while maintaining that the Strait of Hormuz was “closed.”

The sudden return of hostilities shattered the relative calm that had descended on Iran for several days after the U.S. paused daily strikes on the Islamic Republic in order to make room for peace talks.

Iran’s Revolutionary Guards said it had launched strikes on a U.S. air base and military central command center in Jordan, state-run Nour News agency reported early Wednesday, local time. Its navy also struck three oil tankers that it said were “in violation” of its blockade on the Strait off Hormuz, said separately, according to Iran’s state-run news agency IRNA.

In a post on X, U.S. Central Command, or CENTCOM, said it had thwarted an “attempted surprise attack” on forces based in the Middle East at around 5.45 p.m. Tuesday night. All Iranian missiles were successfully intercepted, it said, but troops remained “vigilant and at a high state of readiness.”

Just hours later, CENTCOM said it had launched “precision strikes” in Iraq alongside the Saudi Arabian Armed Forces against “Iran-aligned terrorists” that it said Tehran’s Islamic Revolutionary Guard Corps had directed to attack U.S. forces and Saudi energy infrastructure.

CENTCOM did not name the militias it had targeted, but the Popular Mobilization Forces, a grouping of dozens of mainly Shia pro-Iranian armed factions, said in a post on X that a number of its headquarters in Iraq had been attacked and several members killed. The attack marked a “highly dangerous escalation” in the conflict, as well as a “violation of Iraq’s sovereignty,” the PMF said.

U.S. and Saudi fighters struck multiple logistics and weapons sites across eastern Iraq in a “strong response to over 30 IRGC-directed aerial drone attacks in the last 72 hours,” which it said were “unwarranted,” CENTCOM added.