The operation, known in the Israeli military as “Outside the Box” and widely referred to in the media as “Operation Orchard,” targeted the Al-Kibar site in the Deir ez-Zor region. Shortly before 1 a.m., the Israeli crews transmitted a single codeword: “Arizona,” signalling that the target had been destroyed.

Israel remained silent about the strike for more than a decade. Syria offered little information about the site, while the operation’s details remained largely classified until March 21, 2018, when the Israeli military released documents, photographs and cockpit footage.

The Al-Kibar Reactor in Eastern Syria

The targeted building stood at Al-Kibar, approximately 450 kilometres northeast of Damascus. According to US intelligence briefings to Congress, the facility housed a gas-cooled, graphite-moderated reactor modelled on North Korea’s Yongbyon nuclear complex.

This type of reactor could be used to produce plutonium, a material that can be used in nuclear weapons.

Reports cited in the supplied account said Israeli intelligence obtained photographs of the facility’s interior from a Syrian official’s laptop. One image reportedly showed a senior North Korean nuclear official alongside the head of Syria’s atomic energy commission.

Israeli Prime Minister Ehud Olmert initially asked US President George W. Bush to destroy the facility. Bush preferred a diplomatic approach. In his memoir Decision Points, he later described Olmert’s concerns about the American strategy.

Israel ultimately decided to carry out the strike itself.

Eight Fighter Jets and a Night-Time Strike

According to details released by Israel in 2018, the strike force took off at approximately 10:30 p.m. on September 5, 2007.

The aircraft included F-15I Ra’am fighters from the Israeli Air Force’s 69 Squadron and F-16I Sufa fighters from the 119 and 253 squadrons. Eight aircraft participated in the mission, with four of each type representing the most widely reported breakdown.

The jets carried approximately 17 tonnes of precision-guided munitions, according to figures published by journalist David Makovsky in The New Yorker in 2012. Accounts of the operation describe a combination of laser-guided and GPS-guided weapons, including penetrator munitions.

Shortly before 1 a.m., the crews transmitted the codeword “Arizona.” According to reports, the aircraft returned to base roughly four hours after take-off.

Drop tanks later found in Turkey fuelled speculation that part of the flight route passed through or near Turkish airspace.

How Did Israeli Jets Evade Syrian Defences?

The precise method used to penetrate Syrian air defences has never been officially confirmed by Israel.

A November 2007 report by Aviation Week said a radar installation at Tall al-Abuad was initially targeted through electronic attack and subsequently struck with precision weapons.

Other accounts proposed that Israel used a network-intrusion capability resembling the American Suter system. A report by IEEE Spectrum, citing unnamed European sources, also described an alleged electronic “kill switch” concealed in Syrian radar equipment.

These explanations remain unconfirmed.

Israel did, however, acknowledge that secrecy was a deliberate part of the mission. According to the account, Israeli Air Force chief Eliezer Shkedi directed that the operation should not initially be linked publicly to Israel, with the aim of reducing the risk of war.

Syria denied that the facility was a nuclear reactor. President Bashar al-Assad described it as an incomplete and empty military complex.

In 2011, the International Atomic Energy Agency concluded that the building was “very likely” a reactor that Syria should have declared under its international safeguards obligations.

Why Did Israel Keep the Operation Secret?

The Israeli government’s decision to withhold public acknowledgement was intended, according to the supplied account, to reduce the possibility of a wider conflict.

The strike was also compared with Israel’s 1981 attack on Iraq’s Osirak nuclear reactor, known as Operation Opera. Both operations targeted facilities that Israel viewed as potential nuclear threats.

Al-Kibar differed in one significant respect: Israel kept its role officially unacknowledged for more than ten years.

On March 21, 2018, the Israeli military released declassified documents, photographs and footage of the attack, publicly acknowledging its involvement.

The disclosure also carried a broader strategic message, with the operation widely interpreted as a signal to Iran as well as Syria.

A Strike That Changed the Course of Syria’s Nuclear Programme

Operation Orchard destroyed a facility that international inspectors later assessed was very likely an undeclared nuclear reactor. The strike took place before the reactor became operational, according to the account.

The operation remains a notable example of a state using military force against a suspected nuclear programme while attempting to limit the risk of a broader war through secrecy.

Its full operational details remain contested, particularly the methods used to overcome Syrian air defences. Nevertheless, the 2018 disclosure provided the public with a clearer account of a mission that Israel had kept officially unacknowledged for more than a decade.