The war entered its fourth week on Saturday.
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.
Ayatollah Ali Khamenei was among those killed in Tehran on the first day of strikes and his son Mojtaba Khamenei was chosen to succeed him. Iran is responding with missile and drone attacks targeting Israel, regional U.S. bases and multiple Gulf nations. Iran is also attempting to block some shipping traffic through the Strait of Hormuz.
Israel is also intensifying its long-running strike campaign against the Iran-backed Hezbollah militia in Lebanon.
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Leaders of Canada, France, Germany, Italy and the United Kingdom issued a joint statement expressing deep concern over the escalating conflict between Israel and Hezbollah in Lebanon.
The nations condemned attacks on civilians and called for immediate de-escalation as well as “meaningful engagement … to negotiate a sustainable political solution.”
More Iranian strikes were reported across the region on Monday, including in Abu Dhabi, Qatar, Kuwait, Saudi Arabia and Israel.
Two-hundred U.S. troops have been wounded in the war with Iran so far, including 10 service members who have been “seriously wounded, according to Central Command spokesperson Capt. Tim Hawkins.
Out of the 200 injured, 180 troops have returned to duty, he said.
Wounds include burns, traumatic brain injuries and shrapnel wounds, according to a U.S. official.
Most attacks wounding U.S. troops have been from one-way Iranian attack drones, Joint Chiefs of Staff Chairman Gen. Dan Caine said last week.
-ABC News’ Steven Beynon
Over 1 million people are displaced in Lebanon, with more than 100,000 of those people staying in shelters, according to the nation’s Disaster Risk Management Unit at the Prime Minister's Office.
The Israel Defense Forces on Monday announced a "limited and targeted" ground operation in southern Lebanon, and Israel's Ministry of Defense said that "hundreds of thousands of Shiite residents of South Lebanon who have been evacuated” cannot “return to their homes south of the Litani region until the safety of the residents of the north is guaranteed."
