'Unprecedented': How overwhelming US attack on Iran unfolded
Caine said the attack started with a "single synchronized wave" of aircraft.
It began on Friday with a nine-word order from President Donald Trump: "Operation Epic Fury is approved. No aborts. Good luck."
The order to go prompted a major military operation that had been planned for months and, in some parts, years, to hit Iran with "speed, surprise and violence of action," Gen. Dan Caine, chairman of the Joint Chiefs of Staff, said at a news conference with Secretary of Defense Pete Hegseth on Monday.
Caine said over the last 30 days, military assets were redeployed for the complex operation, including the Gerald R. Ford Carrier Strike Force being moved across the Atlantic from the Western Hemisphere.
He said that in the hours leading up to Saturday's joint U.S-Israel attack on Iran, air-defense batteries were readied throughout the region, pilots rehearsed their strike packages for the final time, crews loaded their aircraft with weapons and two aircraft carriers moved toward their launching points across the globe.
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On Saturday morning, the U.S. Cyber Command and the U.S. Space Command began "layering non-kinetic effects, disrupting and degrading and blinding Iran's ability to see, communicate, and respond at the hour," Caine said, calling the military operation "historic" and "unprecedented."
At 9:45 a.m. Tehran time, 1:15 p.m. ET on Saturday, major combat operations began.
"As dawn crept up across the Central Command AOR [area of responsibility], the skies surged to life," Caine said.
He said more than 100 military aircraft formed a "single synchronized wave" flying to targets across Iran.
Israel Defense Forces said on Sunday that it simultaneously began a mission to decapitate Iran's political and military leadership, killing Iran's Supreme Leader Ayatollah Ali Khamenei and more than 40 top military commanders.
Caine said the first salvos from the United States were Tomahawk missiles unleashed by the U.S. Navy from the sea in a "systematic targeting of Iranian command-and-control infrastructure, naval forces, ballistic missile sites and intelligence infrastructure."
Caine said the opening shots in the operation were "designed to daze and confuse" the Iranian forces.
"The combined impact of these strikes -- swift, precise and overwhelming -- has resulted in the establishment of local air superiority," Caine said. "This air superiority will not only enhance the protection of our forces, but also allow them to continue the work over Iran."
Caine said that over the past two days, the U.S. military has launched hundreds of missions from land and sea.
"This was a massive, overwhelming attack across all domains of warfare, striking more than 1,000 targets in the first 24 hours," Caine said.
He said B-2 bombers flew 37-hour round-trip sorties, launched from the continental United States, "dropped precision, penetrating munitions" on Iranian underground facilities across the southern flank of the country and slightly deeper.
Separately, Israel executed hundreds of missions targeting Iran's Air Force and Navy aircraft, Caine said.
The general said defense across the region was equally strong, as U.S. Patriot and THAAD missile defense systems intercepted hundreds of ballistic missiles targeting U.S. forces.
Adding to the overpowering attack, Caine said the U.S. partners from across the region, including Qatar, the UAE, Kuwait, Jordan and Saudi Arabia, "joined the fight, proving that years of training, trust and hard-earned integration pay off."
On Monday, Hegseth said that while Iran's military has been weakened, it has not been destroyed. He said Iran still has a supply of long-range missiles that the U.S. military is continuing to target.
Neither Caine nor Hegseth would put a timeline on how long the operations will continue in Iran.
"Operations will remain active across the theater and across the globe," Caine said. "The U.S. forces are postured not only to maintain pressure, but to respond and adapt as required."
In a speech on Monday at the White House, President Trump said the operations were initially projected to last four to five weeks, but added, "We’re already ahead of our time projections.”
'We have the strongest and most powerful, by far, military in the world, and we will easily prevail,” Trump said.
Caine issued a warning to any nemesis of the United States contemplating any actions to threaten American interests around the world. He said Operation Epic Fury "stands as a reminder of what the United States military uniquely delivers and the ability to project power on a global scale with speed, surprise, precision and overwhelming force when we as a nation require it."