The US military said it began launching air strikes on Iran early Thursday in 'a powerful response' to Tehran's attempted surprise attacks targeting American forces in Jordan and ships in the Strait of Hormuz as the war reignited and again drawing in the Islamic republic's proxies.

Threat comes as Iranian media report that four Iranians were killed in joint US-Saudi attacks in Iraq.

The strikes also come after the U.S. and Saudi Arabia launched joint airstrikes against Iran-backed militias in Iraq.