As Operation “Midnight Hammer” got underway on Saturday, local time, a group of US B-2 bombers was seen heading toward the Pacific island of Guam.

Experts thought the flights were a possible pre-positioning for any US decision to strike Iran. But they were a decoy.

The real group of seven bat-winged B-2 stealth bombers flew east undetected for 18 hours, keeping communications to a minimum, refuelling in midair, the US military later revealed.

As the bombers neared Iranian airspace, a US submarine launched more than two dozen Tomahawk land attack cruise missiles. US fighter jets flew as decoys in front of the bombers to sweep for any Iranian fighter jets and missiles.

The attack on Iran’s three main nuclear sites was the largest operational strike by B-2 stealth bombers, and the second-longest B-2 operation flown, surpassed only by those following the September 11, 2001, attacks on the US by al Qaeda.

The B-2 bombers dropped 14 bunker-busting GBU-57 Massive Ordnance Penetrators, each weighing 13,600 kilograms. The Pentagon said the operation involved more than 125 US military aircraft.

From the US military’s perspective, the operation was a resounding tactical success. The Iranians were unable to get off a single round at the American aircraft and were caught flat-footed, General Dan Caine, the chairman of the Joint Chiefs of Staff, said at the Pentagon on Sunday.

“Iran’s fighters did not fly, and it appears that Iran’s surface to air missile systems did not see us throughout the mission,” Caine said. “We retained the element of surprise.”

Caine said initial battle damage assessments indicated that all three sites targeted sustained severe damage and destruction. He declined to speculate if any Iranian nuclear capabilities might still be intact.

Satellite image said to show damage to Iran’s Fordo underground nuclear site. Photo: AAP

Caine said the mission came together in just weeks.

President Donald Trump declared a “spectacular military success” and warned “there will be peace, or there will be tragedy for Iran far greater than we have witnessed over the last eight days”.

World waits

While Iran says there is no possible return to diplomacy after the US attack, Washington asserts it is not at war with Iran but with its nuclear program.

With the damage visible from space after the so-called bunker-buster bombs crashed into the mountain above Iran’s Fordo nuclear site, Tehran vowed to defend itself at all costs.

Iran fired another volley of missiles at Israel that wounded scores of people and flattened buildings in Tel Aviv.

But perhaps in an effort to avert all-out war with the US superpower, it is yet to follow through on its main threats of retaliation against the US itself – either by targeting US bases or trying to choke off global oil supplies.

In Istanbul, Iranian Foreign Minister Abbas Araghchi said Tehran would consider all possible responses. There would be no return to diplomacy until it had retaliated, he said.

The UN nuclear watchdog, the IAEA, said no increases in off-site radiation levels had been reported after the US strikes.

Much of Tehran, a capital city of 10 million people, has emptied out, with residents fleeing to the countryside to escape Israeli bombardment.

Iranian authorities say more than 400 people have been killed since Israel’s attacks began, mostly civilians.

Iran has launched missiles back at Israel, killing at least 24 people over the past nine days, the first time its projectiles have penetrated Israel’s defences in large numbers.

Iran nuke access claim

Dmitry Medvedev, deputy head of Russian President Vladimir Putin’s Security Council, said several countries were prepared to supply Tehran with nuclear weapons.

He didn’t specify the nations, but said the US attack caused minimal damage and would not stop Tehran from pursuing nuclear weapons.

Abbas Araghchi said he would fly to Russia, with whom Iran has a strategic partnership, for talks with Putin on Monday.

“The US showed they have no respect for international law. They only understand the language of threat and force,” Araghchi said.

Russia has “strongly condemned” the US attacks.

The “irresponsible decision” to bomb Iran violated international law and the United Nations Charter, the Russian Foreign Ministry in Moscow said on Sunday.

Aus urges de-escalation

“We note the US President’s statement that now is the time for peace,” an Albanese government spokesperson said on Sunday.

“The security situation in the region is highly volatile. We continue to call for de-escalation, dialogue and diplomacy.

“We have been clear that Iran’s nuclear and ballistic missile program has been a threat to international peace and security.”

Questions have been raised over whether Australia – as a US ally – should bolster American efforts in the Middle East.

The federal government has insisted Australia is not a central player in the conflict. It has deployed defence assets to the region only to assist in evacuation efforts, with Foreign Minister Penny Wong repeatedly emphasising they are not there to engage in combat.

The opposition has supported America’s actions in Iran, noting they were intended to prevent the nation from acquiring nuclear weapons.

“The world can never accept a nuclear-armed Iranian regime and today the United States military has taken proactive action to ensure that we never need to,” Opposition Leader Sussan Ley and acting opposition spokesman for foreign affairs Andrew Hastie wrote in a joint statement.

“While Australians will never seek conflict in the world, we can never forget that the Iranian regime is a militantly theocratic autocracy.

“It is the Iranian people who are the victims of this brutal regime and we stand in solidarity with them.”

The casualty toll from US strikes remains unclear but Greens leader Larissa Waters called the event a “terrifying and catastrophic escalation”.

“You cannot bomb your way to peace,” she said.

“Australia must always work for peace and de-escalation. Australia is not powerless, and we cannot be involved in another brutal war in the Middle East.”

About 2600 Australians in Iran are seeking assisted departures from the region, alongside about 1200 in Israel as the government urges travellers not to venture to either nation.

Staff from the Department of Foreign Affairs have evacuated the Tehran embassy and are helping Australians leave through the border in Azerbaijan.

The government is also poised to help citizens leave once airspace over both nations re-opens.

-with AAP