The Iranian cities hit include Tehran, Isfahan, Tabriz, Kermanshah, and Qom, according to Telegram posts from the country's Revolutionary Guard Corps.
Also targeted was the residence of Supreme Leader Ayatollah Ali Khamenei, as well as the nation's intelligence ministry, its defence ministry, and its Atomic Energy Organization, Sky News understands.
Satellite imagery of the leader's compound, taken today, shows black smoke and extensive damage, with at least four buildings struck. An Iranian official said Khamenei was not there at the time.
According to the Iranian Health Ministry, more than 60 students were killed and 80 more injured in another strike at a girls' school in Minab, a city in Hormozgan province.
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Now Iran has hit back, simultaneously striking four US bases across the Middle East.
These were Al Udeid Air Base in Qatar, Al Salem base in Kuwait, Al Dhafra Air Base in the United Arab Emirates, and the US Fifth Fleet base in Bahrain.
The attack on the US Navy's Fifth Fleet centre was also reported by Bahraini state news agency BNA.
Sky correspondent Sally Lockwood further reports that a loud explosion had been heard in Dubai.
At least one person has been killed in the UAE. Another four were killed in Syria, when a missile struck a building in the south of the country, the state-owned SANA news agency reported.
There have been no reported American casualties, two officials told our US partner NBC News
The Revolutionary Guard said it considers "all US bases, resources, and interests in the region to be legitimate targets" for retaliation.
Sky News' Europe correspondent Alistair Bunkall has warned that the Tehran regime "will not roll over and will die fighting if needs be."
It comes after Donald Trump confirmed "major combat operations" against Iran in an eight-minute video on Truth Social.
He also urged the Iranian people to rise up against the ruling regime, saying: "When we are finished, take over your government, it will be yours to take".
The initial noises were positive. Conversations that I had with figures involved in those negotiations were optimistic that the sides were drawing close to a provisional agreement, although some obvious and significant gaps remained.
Notably, one issue that wasn't discussed was Iran's ballistic missile programme - which alarmed the Israelis because of the threat those missiles pose to them.
US and Israel strike Iran - follow latest
On Friday morning, Oman's foreign minister Badr Albusaidi, who has mediated several rounds of talks, including those in Geneva, flew to Washington at short notice to brief US vice president JD Vance in person.
Albusaidi then gave two extremely rare interviews on US television to explain what was on the table. It was a desperate and honest attempt to keep the sides talking.
But there were already signs that things were unravelling.
Mike Huckabee, the US ambassador to Israel, sent an email to embassy staff on Friday morning warning them that if they wanted to leave the country they "must do so TODAY".
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It had an air of unplanned urgency, rather than a controlled diplomatic evacuation.
Perhaps they had just learnt something was imminent. Maybe Netanyahu, who has always been deeply sceptical of negotiations, had already decided to attack.
British diplomats were relocated from Tel Aviv to Jerusalem, as they were during the 12-Day War last June. Western embassies and military outposts around the region were emptied of non-essential staff.
Then late on Friday evening I started to hear word of a possible attack overnight. From my own experience of multiple Middle East wars, it's very hard to pick out the truth from a wall of noise, but the signs were clearly bleak.
The cork is now out of the bottle.
President Trump, with the help of Israel, is going for regime change. It's all or nothing.
Iran's ability to respond might be limited, following the attack on its ballistic missile sites last summer, but already strikes have been reported across the Middle East, not just Israel.
The Iranian regime won't roll over; they will die fighting and will drag the region into a wider conflict if needs be.
The US commander in chief - who came to power as an arch opponent of the US's so-called "forever wars" - has set out ambitious and extensive goals for his attack against the Islamic Republic, saying he plans to prevent this "wicked, radical dictatorship" from threatening the United States.
But he is not in complete control of events.
Mr Trump is gambling that overwhelming US military firepower from the air - rather than boots on the ground - will be enough to destroy the Iranian regime. Tehran's military may have been degraded by previous US and Israeli strikes, but they are showing no sign of rolling over.
It retains the ability to inflict significant harm against Israel as well as US forces in the region - and is already fighting back.
The scale of that retaliation and how much the US and Israel can withstand the counterattacks will be a fundamental indicator to track.
Mr Trump has prepared his country for the potential for American service men and women to be killed, saying in his video address "we may have casualties. That happens in war".
He has calculated that any pain the US side suffers is worthwhile to end the threat posed by Iran.
And he spelt out these objectives - a move that could come back to haunt him if they are not achieved.
Chief among these war goals is a vow to prevent Iran from ever having nuclear weapons. But the US president has also pledged to destroy Iran's missile capabilities and to "annihilate" its navy.
He issued an ultimatum to all members of the Iranian armed forces and security services from the Republican Guard to the police, telling them to lay down their weapons "or face certain death".
There is no indication that the Iranian security forces are about to betray the regime.
The fact that Iran is now retaliating by launching missiles against Israel is a clear sign that Tehran has not been cowed by Mr Trump's opening salvo and is ready to fight.
Even if the regime is toppled, the next moment of peril is what comes next.
The US president made clear that he wants the Iranian people to step up and "take over your government".
But, again, he does not have the ability to control what that would look like and whether what comes next is better than what he seeks to destroy.
The history of wars in the Middle East shows that no plan by either side survives first contact with the enemy.
But after Saturday's co-ordinated attacks from the US and Israel, he faces possibly his gravest threat yet.
The threat is greater, even, than when thousands of his own citizens rose up against his regime in the winter just past.
Iran claims Mr Khamenei was not in Tehran when the US and Israel struck his compound overnight, and that he has been transferred to a secure location.
But, who is the supreme leader?
Mr Khamenei was born into a clerical family in 1939 in Iran's second-largest city Mashhad.
He received a religious education there before turning his attention to political activities against the Shah - the country's royal ruler until the 1979 Iranian Revolution.
Mr Khamenei eventually went into exile in the 1960s, only re-emerging after the Shah was overthrown.
He was a close confidante of the leader who emerged after the revolution - Ayatollah Ruhollah Khomeini - and Mr Khamenei quickly rose through the ranks of government.
After other key political figures were assassinated - with Mr Khamenei himself targeted in a separate attempt, leaving him paralysed in his right arm - he became president of Iran in an uncontested election.
US and Israel strike Iran - follow live
He eventually succeeded Mr Khomeini after his death in 1989, becoming supreme leader.
Mr Khamenei was appointed by the 88-person Assembly of Experts, whose members are elected but vetted by the 12-person Guardian Council - of which Mr Khamenei appoints six members.
The Guardian Council, a clerical body, also vets candidates for presidential and parliamentary elections.
In theory, the council oversees the republic to ensure it complies with Islamic law.
In reality, the supreme leader carefully manages the existing system to balance competing interests, advance his own priorities and ensure that no one challenges the Islamic Republic or his leadership.
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His 35-year reign over Iran also means his influence extends across the Middle East, given Iran's backing of Hamas and Hezbollah.
The death of Ebrahim Raisi, Iran's president, in a helicopter crash in May 2024 posed a major issue for the supreme leader.
Mr Raisi was replaced by Masoud Pezeshkian as Iran's president following his death.
Mr Raisi had been seen as the main candidate to succeed the 86-year-old Mr Khamenei.
His death meant that Mr Khamenei's son, Mojtaba Khamenei, was more likely to become the successor.
The Republic was founded as an alternative to a monarchy after the 1979 Revolution, with leaders portraying their system as superior to both Western democracies and military dictatorships and monarchies across the Middle East.
However, many Iranians already view the state as a corrupt and dictatorial regime.
This isn't the only reason some Iranians are unhappy with his leadership. Western sanctions linked to the country's nuclear programme have devastated its economy.
Iranians responded in the shape of the mass protests which erupted across the country in December 2025 and January this year.
Demonstrations, which had begun over grievances of economic hardship and political disenfranchisement, quickly grew into widespread anti-government unrest.
Iranian security forces responded with a brutal crackdown, killing thousands of protesters.
Estimates from human rights organisations and doctors ranged from more than 5,000 at the conservative end to 33,000 by one count, and even as high as 50,000, according to one unverified claim.
Words including "Zionist war criminal", "Stop the Genocide" and "Free Palestine" were sprayed in red paint on the bronze statue in Parliament Square in Westminster in the early hours of Friday.
Caspar San Giorgio, 38, of no fixed address, was arrested shortly after 4am on Friday, police said.
He was taken into custody and charged at 3.50am on Saturday.
He was remanded and is due to appear at Highbury Corner Magistrates' Court.
San Giorgio was also arrested on suspicion of supporting Palestine Action, which is a proscribed organisation, under the Terrorism Act, the Metropolitan Police said on Friday.
The statue was cordoned off and work to clean it began on Friday.
Further graffiti read "Never again is Now" and "Globalise the Intifada".