Deep beneath a mountain, hundreds of centrifuges spin, enriching Iran’s uranium that Israel suspects is destined for a nuclear weapon.
The Fordow plant is protected by tonnes upon tonnes of dirt and rock, far away from prying eyes – and foreign missiles.
But as Israeli warplanes fly unchecked above Tehran, with much of the Islamic Republic’s air defences turned to smoking ruins on the ground, attention has moved to the secretive facility.
Some say only the American B-2 stealth bomber and its massive payload could breach the so-called “nuclear mountain”, while others argue troops on the ground might be able to infiltrate its corridors. Or maybe it is simply impossible, short of a nuclear strike.
Iran has repeatedly denied that it is seeking a nuclear weapon and the head of the UN’s nuclear watchdog said in June that it has no proof of a “systematic effort to move into a nuclear weapon”.
Image: A satellite image shows the Fordow nuclear facility. Pic: Maxar Technologies/Reuters
What is the Fordow facility?
The Fordow enrichment plant is one of three key pieces of nuclear infrastructure in Iran – the others being the Natanz enrichment plant and research facilities in Isfahan.
It is thought to be buried around 80m deep into the side of the mountain. It was previously protected by Iranian and Russian surface-to-air missile systems, but these may have wholly or partially knocked out during Israel’s recent attacks.
Construction is believed to have started in around 2006 and it first became operational in 2009 – the same year Tehran publicly acknowledged its existence.
Image: Key sites at Fordow including tunnel entrances
In November 2020, it was believed there were 1,057 centrifuges at Fordow. These are used to separate isotopes and increase the concentration of uranium-235, needed for nuclear fuel and weapons.
In 2023, the International Atomic Energy Agency (IAEA) – the nuclear watchdog – found uranium particles enriched to 83.7% purity – near the 90% needed for a bomb – at Fordow, the only Iranian facility where this has been found.
In June 2024, the Washington Post reported on a major expansion at Fordow, with nearly 1,400 new centrifuges earmarked for the subterranean facility.
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Israel has made no secret of its desire to cripple or remove Iran’s nuclear programme, describing it as an existential threat.
There is much that remains elsewhere in Iran that is capable of producing and using nuclear material.
“But of course the real big piece remains at Fordow still and this has been in the headlines quite a bit,” says Dr Alexander Bollfrass, an expert on nuclear weapons from the International Institute for Strategic Studies (IISS) thinktank.
There is also the chance that an increased focus on diplomacy brings the war to an end before the IDF can make a run at Fordow.
Image: Centrifuge machines at Natanz – similar to ones held at Fordow. Pic: AP
Could bunker buster bombs be used?
There has been a lot of talk about bunker buster bombs. These are munitions that explode twice – once to breach the ground surface and again once the bomb has burrowed down to a certain depth.
The Israelis used 60 to 80 of them in the strike that killed Hezbollah leader Hassan Nasrallah in September last year, according to Martin “Sammy” Sampson, a former air marshal and executive director at the IISS.
But Nasrallah was only 10-15m underground, Mr Sampson said, while Fordow is believed to be 80m beneath the surface.
“An awful lot of planes would be in the same place for an awful long time” to drop enough bombs to have a chance of getting to the buried facility, he added.
Image: A GBU-57 bunker buster bomb seen in 2023. File pic: US Air Force/AP
There is also the possibility that the US, which operates the much more powerful GBU-57 bomb, could assist with any operation at Fordow.
“My sense is that it would still take multiple strikes,” Mr Sampson said, putting it in “more and more unknown territory”.
“It would be pretty disastrous… if you put 400 planes over the top of Fordow, or you put the might of the US over Fordow, and it survived.”
Israel’s ‘contingencies’ for dealing with Fordow
Israel has suggested that it could destroy or cripple Fordow without using bombs dropped from the air.
Israel’s ambassador to the US, Yechiel Leiter, said last weekend that Israel has “a number of contingencies… which will enable us to deal with Fordow”.
“Not everything is a matter of, you know, taking to the skies and bombing from afar,” he told ABC News.
There has been talk of using special forces to raid the facility on the ground, but that has its downsides as well.
“This would be an incredibly high risk mission if you were to do something on the ground,” said Mr Sampson.
There is also the possibility Israel could replicate what happened at the Natanz enrichment plant, where the IAEA said 15,000 centrifuges were likely destroyed in the IDF bombardment of Iran.
This was possibly due to an Israeli airstrike disrupting the power supply to the centrifuges, rather than actual physical damage to the centrifuge hall, according to the nuclear watchdog.
Donald Trump has agreed to send “top of the line weapons” to NATO to support Ukraine – and threatened Russia with “severe” tariffs if it doesn’t agree to end the war.
Speaking with NATO secretary general Mark Rutte during a meeting at the White House, the US president said: “We’ve made a deal today where we are going to be sending them weapons, and they’re going to be paying for them.
“This is billions of dollars worth of military equipment which is going to be purchased from the United States,” he added, “going to NATO, and that’s going to be quickly distributed to the battlefield.”
Weapons being sent include surface-to-air Patriot missile systems and batteries, which Ukrainehas asked for to defend itself from Russian air strikes.
Image: Pic: Reuters
Mr Trump also said he was “very unhappy” with Russia, and threatened “severe tariffs” of “about 100%” if there isn’t a deal to end the war in Ukraine within 50 days.
The White House added that the US would put “secondary sanctions” on countries that buy oil from Russia if an agreement was not reached.
It comes after weeks of frustration from Mr Trump against Vladimir Putin’s refusal to agree to an end to the conflict, with the Russian leader telling the US president he would “not back down”from Moscow’s goals in Ukraine at the start of the month.
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Trump says Putin ‘talks nice and then bombs everybody’
During the briefing on Monday, Mr Trump said he had held calls with Mr Putin where he would think “that was a nice phone call,” but then “missiles are launched into Kyiv or some other city, and that happens three or four times”.
“I don’t want to say he’s an assassin, but he’s a tough guy,” he added.
After Mr Trump’s briefing, Russian senator Konstantin Kosachev said on Telegram: “If this is all that Trump had in mind to say about Ukraine today, then all the steam has gone out.”
Meanwhile, Mr Zelenskyy met with US special envoy Keith Kellogg in Kyiv, where they “discussed the path to peace” by “strengthening Ukraine’s air defence, joint production, and procurement of defence weapons in collaboration with Europe”.
He thanked both the envoy for the visit and Mr Trump “for the important signals of support and the positive decisions for both our countries”.
At least 30 people have been killed in the Syrian city of Sweida in clashes between local military groups and tribes, according to Syria’s interior ministry.
Officials say initial figures suggest around 100 people have also been injured in the city, where the Druze faith is one of the major religious groups.
The interior ministry said its forces will directly intervene to resolve the conflict, which the Reuters news agency said involved fighting between Druze gunmen and Bedouin Sunni tribes.
It marks the latest episode of sectarian violence in Syria, where fears among minority groups have increased since Islamist-led rebels toppled President Bashar al Assad in December, installing their own government and security forces.
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In March, Sky’s Stuart Ramsay described escalating violence within Syria
The violence reportedly erupted after a wave of kidnappings, including the abduction of a Druze merchant on Friday on the highway linking Damascus to Sweida.
Last April, Sunni militia clashed with armed Druze residents of Jaramana, southeast of Damascus, and fighting later spread to another district near the capital.
But this is the first time the fighting has been reported inside the city of Sweida itself, the provincial capital of the mostly Druze province.
The Syrian Observatory for Human Rights (SOHR) reports the fighting was centred in the Maqwas neighbourhood east of Sweida and villages on the western and northern outskirts of the city.
It adds that Syria’s Ministry of Defence has deployed military convoys to the area.
Western nations, including the US and UK, have been increasingly moving towards normalising relations with Syria.
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UK aims to build relationship with Syria
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Concerns among minority groups have intensified following the killing of hundreds of Alawites in March, in apparent retaliation for an earlier attack carried out by Assad loyalists.
That was the deadliest sectarian flare-up in years in Syria, where a 14-year civil war ended with Assad fleeing to Russia after his government was overthrown by rebel forces.
The city of Sweida is in southern Syria, about 24 miles (38km) north of the border with Jordan.
The man convicted of the murder of British student Meredith Kercher has been charged with sexual assault against an ex-girlfriend.
Rudy Guede, 38, was the only person who was definitively convicted of the murder of 21-year-old Ms Kercher in Perugia, Italy, back in 2007.
He will be standing trial again in November after an ex-girlfriend filed a police report in the summer of 2023 accusing Guede of mistreatment, personal injury and sexual violence.
Guede, from the Ivory Coast, was released from prison for the murder of Leeds University student Ms Kercher in 2021, after having served about 13 years of a 16-year sentence.
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Since last year – when this investigation was still ongoing – Guede has been under a “special surveillance” regime, Sky News understands, meaning he was banned from having any contact with the woman behind the sexual assault allegations, including via social media, and had to inform police any time he left his city of residence, Viterbo, as ruled by a Rome court.
Guede has been serving a restraining order and fitted with an electronic ankle tag.
The Kercher murder case, in the university city of Perugia, was the subject of international attention.
Ms Kercher, a 21-year-old British exchange student, was found murdered in the flat she shared with her American roommate, Amanda Knox.
The Briton’s throat had been cut and she had been stabbed 47 times.
Image: (L-R) Raffaele Sollecito, Meredith Kercher and Amanda Knox. File pic: AP
Ms Knox and her then-boyfriend, Raffaele Sollecito, were placed under suspicion.
Both were initially convicted of murder, but Italy’s highest court overturned their convictions, acquitting them in 2015.