"From now on, every American civilian and military personnel in the region will be considered a legitimate target," Iran's state broadcaster said in reaction to the US airstrikes on three Iranian nuclear sites.
US lawmakers almost instantly reacted on social media to the US President's shock announcement he had ordered an attack on Iran, with Republican hawks celebrating the move and the other side of the aisle voicing sharp disapproval.
"Good. This was the right call," US Senator Lindsey Graham said.
"The regime deserves it. Well done, President @realDonaldTrump. To my fellow citizens: We have the best Air Force in the world."
Republicans have generally urged a hard line on Iran. Most consistently back Israeli military operations in the region and have been vocal critics of Tehran's policies.
Texas congressman Dan Crenshaw urged people to back Trump: Support President Trump. You think these decisions were easy? They weren’t. You think this means WW3? You’re wrong. You think it means American soldiers deploying to Iran? You’re wrong."
"You think it means long term stability in the Middle East and a safer future for Americans? You’re right. Because the regime that wanted ‘Death to the Great Satan’ is at its end."
Democrats have been reticent about Trump's two-month-old diplomatic effort with Iran, quietly backing its goal to deprive Iran of a nuclear weapon capability.
But criticism of a potential attack by Democrats had ramped up in recent days and early condemnation by party members was sharp.
"Trump is acting fully outside of his authority and is once again trampling on the Constitution. This is an illegal and terrifying escalation," Representative Summer Lee said.
"Dropping bombs on Iran brings us closer to war, not peace, and he is putting millions of lives at stake. Congress must immediately pass our War Powers Resolution to rein him in."
"This is insane," Massachusetts Democratic representative Jim McGovern spluttered.
"Trump just bombed Iran without Congressional approval, illegally dragging us into war in the Middle East. Have we not learned our lesson!?!?"
A rare maverick on the Democratic side is Pennsylvania Democratic Senator John Fetterman, among the chamber's biggest backers of Israel.
"As I’ve long maintained, this was the correct move by @POTUS. Iran is the world’s leading sponsor of terrorism and cannot have nuclear capabilities," he said.
"I’m grateful for and salute the finest military in the world."
"A few hours ago, after the activation of Qom's air defense and the identification of hostile targets, part of the area surrounding the Fordow nuclear site came under enemy aerial attack," said the crisis management chief of Qom in central Iran.
Air defense systems were activated earlier today in the cities of Isfahan and Kashan in response to the detection of hostile targets, said Isfahan’s deputy governor for security affairs.
The official confirmed that multiple explosions were heard in both Isfahan and Natanz around the same time.“We witnessed hostile incursions near the nuclear facilities in Isfahan and Natanz."
US President Donald Trump on Saturday launched the most serious ever US attack on its Mideast arch-nemesis Iran on Saturday, saying air strikes had hit three nuclear facilities including the underground nuclear site Fordow but calling for peace.
"We have completed our very successful attack on the three Nuclear sites in Iran, including Fordow, Natanz, and Esfahan," Trump said on Saturday.
Trump had hinted at a potential intervention for days and US bunker-busting bombs are widely viewed as the only ordnance capable of penetrating the underground Fordow site.
"All planes are now outside of Iran air space. A full payload of BOMBS was dropped on the primary site, Fordow," he added in a post on Truth Social.
"All planes are safely on their way home. Congratulations to our great American Warriors. There is not another military in the World that could have done this. NOW IS THE TIME FOR PEACE!"
Israel launched a surprise attack on Iran last week which has drawn Iranian missile fire, and Trump mooted possible US involvement, urging Tehran to resolve its nuclear impasse with Washington through talks.
Iranian Foreign Minister Abbas Araghchi said Iran would not negotiate under fire but wanted to pursue diplomacy.
Tehran has repeatedly vowed to target the substantial US military presence in the region if it comes under direct attack.
"This is an historic moment for the United States of America, Israel, and the world. Iran must now agree to end this war," Trump added in another post.
B-2 bombers were used in the US attacks against Iran's nuclear facilities, Reuters reported citing a US official.
The US had informed Israel in advance about the attack on Iran and the matter was coordinated, Walla News reported citing a senior Israeli official.
US President Donald Trump announced US forces had attacked Iranian nuclear sites on Saturday, ramping up the biggest Mideast flare-up among major powers in over twenty years.
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