He is the son of assassinated Supreme Leader Ayatollah Ali Khamenei.
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 by airstrikes in Tehran on the first day of strikes. His successor is yet to be named.
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.
(Read previous Iran live updates here.)
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The death toll from Israeli strikes on Lebanon rose to 50 people as of Tuesday evening, according to the country's Health Ministry.
Another 335 people have been wounded since Israel began intensifying strikes across the country -- including in the capital Beirut -- on Monday, health officials said.
-ABC News' Ghazi Balkiz and Will Gretsky
The Israeli military launched an assault overnight on buildings affiliated with Iran’s internal security forces, with the Israeli Air Force carrying out "an additional wave of airstrikes targeting regime-affiliated sites across Tehran," the Israel Defense Forces said.
Airstrikes targeted "dozens" of sites connected to those forces, IDF spokesperson Avichay Adraee said in a post in Arabic on social media early on Wednesday.
The IDF said it dropped "numerous" munitions on headquarters belonging to the Basij Militia, forces that had been employed by the former supreme leader in quelling domestic unrest.
"These headquarters were used by the Iranian regime to maintain its stability and tighten its control across various parts of Iran by shaping the operational situation picture," Adraee said.
He added, "Additionally, the Supply and Logistics Directorate affiliated with the regime's Ground Forces was targeted, along with missile launch platforms and defensive systems."
Strike’s on infrastructure related to the Iranian regime were expected to "continue to deepen," he said.
