No one was injured, according to the Qatari Ministry of Defense.
President Donald Trump announced "major combat operations" against Iran on Saturday, with daytime strikes in the joint U.S.-Israel attack targeting military and government sites, officials said.
On Sunday, Iranian state television confirmed that Ayatollah Ali Khamenei was among those killed by airstrikes in Tehran on Saturday.
Iran is responding to the U.S.-Israeli operation with missile and drone attacks targeting Israel, regional U.S. bases and Gulf nations. American diplomatic facilities have also been attacked.
In Lebanon, Israel is intensifying its long-running strike campaign against the Iranian-aligned Hezbollah militia.
Watch special coverage on Nightline, "War with Iran," each night on ABC and streaming on Disney+ and Hulu.
U.S. Central Command said on social media that B-1 bombers "struck deep inside Iran to degrade Iranian ballistic missile capabilities” on Sunday night. This follows the use of B-2 stealth bombers on Saturday night.
Eighteen U.S. service members have been seriously wounded as part of the military operation against Iran, according to CENTCOM spokesperson Capt. Tim Hawkins.
Earlier Monday, CENTCOM announced the death of a fourth U.S. service member. Two U.S. officials have told ABC News that the service member was killed in Sunday's attack in Kuwait.
At Monday morning’s Pentagon news conference, Joint Chiefs of Staff Chairman Gen. Dan Caine told reporters that the fatalities and injuries had come from an attack on a tactical operations center.
-ABC News' Luis Martinez
President Donald Trump said at the White House that he grieves for the four U.S. service members who have been killed.
“In their memory, we continue this mission with ferocious, unyielding resolve to crush the threat this terrorist regime poses to the American people,” he said.
“We have the strongest and most powerful -- by far -- military in the world, and we will easily prevail,” he said.
As for a timeline, Trump said the U.S. is “already substantially ahead of our time projections, but whatever the time is, it's OK.”
“From the beginning, we projected four to five weeks, but we have capability to go far longer than that,” he said.
“The United States military continues to carry out large-scale combat operations in Iran to eliminate the grave threats posed to America by this terrible, terrorist regime," President Donald Trump said Monday in his first public remarks since the strikes on Iran began Saturday.
Trump said Iran’s nuclear program was obliterated in "Operation Midnight Hammer," the U.S. strikes on Iran in June 2025. He said the U.S. “warned Iran not to make any attempt to rebuild at a different location, because they were unable to use the ones we so powerfully blew up.”
“But they ignored those warnings and refused to cease their pursuit of nuclear weapons,” Trump said at the White House. “In addition, the regime's conventional ballistic missile program was growing rapidly and dramatically, and this posed a very clear, colossal threat to America and our forces stationed overseas. The regime already had missiles capable of hitting Europe and our bases, both local and overseas, and would soon have had missiles capable of reaching our beautiful America."
"An Iranian regime armed with long-range missiles and nuclear weapons would be an intolerable threat to the Middle East, but also to the American people," he said. "Our country itself would be under threat, and it was very nearly under threat."
