Iran has launched retaliatory missile and drone strikes on Israel, killing at least three people and wounding dozens. Israel's assault used planes as well as drones smuggled into the country in advance, according to officials, to assault key facilities and kill senior generals and scientists.
Iran's UN ambassador said 78 people had been killed and more than 320 wounded in the attacks that targeted the heart of Tehran's nuclear programme.
Israel claims the barrage was necessary before Iran got any closer to building a nuclear weapon, although experts and the US government have assessed that Tehran was not actively working on such a weapon.
The Israeli military urged civilians to head for cover in bomb shelters around the country from late on Friday as Iran retaliated by launching waves of drones and ballistic missiles at Israel.
Israel's military said more drones were intercepted near the Dead Sea early Saturday. A hospital in Tel Aviv treated seven people wounded in the second Iranian barrage. All but one of them had light injuries. Israel's Fire and Rescue Services said they were wounded when a projectile hit a building in the city. A spokesperson for Beilinson Hospital said one woman was killed.
Hours later, an Iranian missile struck near homes in the central Israeli city of Rishon Lezion, killing two more people and wounding 19, according to Israel's paramedic service Magen David Adom. Israel's Fire and Rescue service said four homes were severely damaged.
Meanwhile, the sound of explosions and air defence systems firing at targets echoed across central Tehran shortly after midnight on Saturday.
Iran's semi-official Tasnim news agency reported a fire at Tehran's Mehrabad International Airport. A video posted on X showed a column of smoke and flames rising from what the outlet said was the airport.
The Israeli military said it carried out overnight strikes on dozens of targets including air defences "in the area of Tehran".
Countries in the region condemned Israel's attack, while leaders around the globe called for immediate de-escalation from both sides.
Israel had long threatened such a strike, and successive American administrations sought to prevent it, fearing it would ignite a wider conflict across the Middle East and possibly be ineffective at destroying Iran's dispersed and hardened nuclear programme.
But developments triggered by Hamas's October 7 2023 attack - plus the re-election of US President Donald Trump - created conditions that allowed Israel to follow through on its threats. Prime Minister Benjamin Netanyahu said the US was informed in advance of the attack.
On Thursday, Iran was censured by the UN's atomic watchdog for not complying with obligations meant to prevent it from developing a nuclear weapon.
The crossfire between Israel and Iran disrupted East-West travel through the Middle East, a key global aviation route, but Jordan's state-run Petra news agent said the country was reopening its air space to civilian aircraft on Saturday morning, signalling it believes there is no immediate danger.
Among the key sites Israel attacked was Iran's main nuclear enrichment facility in Natanz, where black smoke could be seen rising into the air. It also appeared to strike a second, smaller nuclear enrichment facility in Fordo, about 60 miles south east of Tehran, according to an Iranian news outlet close to the government that reported hearing explosions nearby.
Israel said it also struck a nuclear research facility in Isfahan and destroyed dozens of radar installations and surface-to-air missile launchers in western Iran. Iran confirmed the strike at Isfahan.
Yossi Beilin, Former Israeli Justice Minister, who initiated the 1993 Oslo Accords, told LBC News: "[Iran] are not recognising our existence and they are not ready to talk to us and we don't talk to each other...we cannot negotiate with them."
UN nuclear chief Rafael Grossi told the Security Council that the above-ground section of the Natanz facility had been destroyed. The main centrifuge facility underground did not appear to have been hit, but the loss of power could have damaged the infrastructure there, he said.
Mr Netanyahu said the attack was months in the making and had been planned for April before being postponed.
Israel's Mossad spy agency positioned explosive drones and precision weapons inside Iran ahead of time, and used them to target Iranian air defences and missile launchers near Tehran, according to two security officials.
Among those killed were three of Iran's military leaders: General Mohammad Bagheri, who oversaw the entire armed forces; General Hossein Salami, who led the paramilitary Revolutionary Guard; and General Amir Ali Hajizadeh, head of the Guard's ballistic missile programme.