Israel has carried out dozens of airstrikes on Iran and has declared an emergency as it braces for retaliation.
Its military said a “pre-emptive, precise, combined offensive based on high-quality intelligence” had been launched – called Operation Rising Lion.
“Dozens of IAF jets completed the first stage that included strikes on dozens of military targets, including nuclear targets in different areas of Iran,” said a statement.
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Prime Minister Benjamin Netanyahu said the attack was to “roll back the Iranian threat to Israel‘s very survival” and would last for “as many days as it takes to remove the threat”.
Iranian state media reported the head of the country’s powerful Revolutionary Guard, Hossein Salami, had been killed.
Mehr News said nuclear scientist Fereydoun Abbasi was also dead, as was theoretical physicist Dr Mohammed Mehdi Tehranchi and Major General Gholam Ali Rashid.
State media reported explosions northeast of capital Tehran early on Friday, and said buildings belonging to the armed forces were hit in the Mahalati complex north of the city.
The country’s Supreme leader, Ayatollah Ali Khamenei, warned of “severe punishment” and claimed residential areas had been targeted.
“In the enemy’s attacks, a number of commanders and scientists were martyred. Their successors and colleagues will immediately continue their duties,” said a statement reported by the Tasnim news agency.
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Iran TV shows bomb damage
The international atomic watchdog, the IAEA, said Iran’s uranium enrichment facility at Natanz – in central Isfahan province – was one of the facilities targeted and that it’s in contact with Iranian authorities about radiation levels.
The exact locations of the other sites attacked are still to be confirmed
A “special state of emergency” is now in effect in Israel, said its defence minister, who warned a “missile and drone attack… is expected in the immediate future”.
Israelis were woken in the early hours by air raid sirens and a phone alert warning there could be “severe retaliation”, said Sky’s Middle East correspondent Alistair Bunkall.
An IDF statement said authorities are “prepared for a wide range of scenarios in defense and offense that may be needed”.
US secretary of state Marco Rubio said America was not involved and Israel believed the strikes were necessary for its self defence.
He said “necessary steps” had been taken to protect US forces in the region.
“Let me be clear: Iran should not target US interests or personnel,” Mr Rubio warned.
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Netanyahu announces Operation Rising Lion
The attack comes amid fears over Iran’s nuclear programme, with a warning this week the country is breaking its obligations for the first time in 20 years.
Israel and the US have long feared Iran is plotting to develop a nuclear weapon. Tehran has repeatedly denied this and insists its programme is for civilian purposes.
Mr Netanyahu’s video statement on Friday claimed Iran had in recent years developed enough highly enriched uranium for “nine atom bombs”.
“In recent months, Iran has taken steps that it has never taken before – steps to weaponize this enriched uranium,” said the prime minister
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Mr Netanyahu added: “If not stopped, it could produce a nuclear weapon in a very short time. It could be a year, it could be a few months.
“This is a clear and present danger to Israel’s very survival.”
US and Iranian officials were scheduled to hold a sixth round of talks on Tehran’s escalating uranium enrichment programme in Oman on Sunday.
President Trump said earlier on Thursday an Israeli strike on Iran “could very well happen” but that he hoped for a peaceful resolution.