The U.S. military launched airstrikes on July 19 targeting Iran's paramilitary Revolutionary Guard to retaliate for the killing of American troops in Jordan, further widening crossfire between the nations as an interim deal seeking an end to their war has collapsed.

The strikes came as a new statement attributed to Iran’s supreme leader Mojtaba Khamenei warned of “unforgettable lessons” for the United States.

The US military says two of its personnel were killed in Jordan and another is missing after an Iranian attack, while Iran's supreme leader said Washington would pay for "seeking…