Sgt. Benjamin N. Pennington, 26, was killed in Saudi Arabia.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israel strikes attack targeting military and government sites, officials said.
Iranian state television confirmed that Ayatollah Ali Khamenei was among those killed in Tehran on the first day of strikes. His son Mojtaba Khamenei was chosen on Sunday to succeed him.
Iran is responding to the operation with missile and drone attacks targeting Israel, regional U.S. bases and multiple Gulf nations. Israel is also intensifying its long-running strike campaign against the Iran-backed Hezbollah militia in Lebanon.
------
For updates in Spanish, click here.
Iranian President Masoud Pezeshkian and Supreme Leader Ayatollah Ali Khamenei are "safe and sound," Foreign Ministry Spokesperson Esmaeil Baghaei told ABC News.
Earlier Saturday, Israel said it had "eliminated ... several senior officials' in Iran but provided no further details.
At least 201 people had been killed and 747 others injured across Iran as of Saturday evening local time, a spokesperson for the Iranian Red Crescent Society told Iranian media.
Rescue crews have been active in 24 provinces and relief is actively being provided, the spokesperson further said.
So far no serious injuries have been reported among U.S. personnel involved in the ongoing strikes against Iran, according to a U.S. official.
-ABC News' Luis Martinez
Kuwait's Civil Aviation Authority confirmed that a drone targeted the Kuwait airport, "resulting in minor injuries to a number of workers, in addition to limited material damage to the passenger building."
"The Authority confirmed that the situation is under complete control by the concerned authorities in the country, and that the safety of passengers and workers represents the utmost priority," the statement also said.
