Israel has formally admitted to its role in a decade-old airstrike that destroyed a Syrian nuclear facility allegedly built with help from North Korea.

The September 2007 strike against the Al-Kibar nuclear reactor in the eastern desert of Syria’s Deir al-Zour province was widely reported to be an operation by the Israeli air force at the time, but the Israeli government has never formally acknowledged its role in the strike until now.

Accounts provided by the Israeli Defense Forces (IDF) show that two waves of Israeli F-15I and F-16I jets participated in the late-night attack against the suspected reactor over a period of four hours. Planners timed the strike to take place before the reactor went into operation to prevent a potential radiological incident that could have caused environmental damage to the region.

Israeli Chief of the General Staff Lt. Gen. Gadi Eisenkot described the strike as “the most momentous attack since the Yom Kippur War in Syria.” In an interview released by the IDF, he explained that the Israeli military planned the operation in intense secrecy, concealing preparations from its own forces with a cover story about operational readiness exercises. Eisenkot said he estimated the strike had a 10 to 15 percent chance of prompting a wider war with Syria, but recommended against preparations for a broader conflict to maintain the element of surprise.

As part of the declassification of the Al-Kibar raid, Israeli authorities released satellite imagery of the facility before and after the strike, snippets of footage from the jets involved in the attack, and allowed “Colonel Amir,” an F-15 pilot involved in the attack on the facility, to participate in a video interview with Israel’s Haaretz newspaper with his face partially obscured by the visor of a flight helmet.

“We understood the historical significance of this moment,” Amir told Haaretz. “We all learned about the attack on the Iraqi nuclear reactor in 1981, the Opera Operation, and we all knew it by heart. And this was the next time that the State of Israel decided to attack a nuclear reactor and we understood completely the significance and what is the meaning for the future of the State of Israel.”

Israel first approached the U.S. with intelligence about Al-Kibar in the spring of 2007, after Israel spies had reportedly broken into the residence of the head of Syria’s Atomic Energy Commission in Vienna and hacked his laptop. Photos of the inside of Al-Kibar recovered from the laptop—along with satellite imagery and a stream of intelligence about Syrian visits to North Korea’s reactor and North Korea’s procurement activities dating back to 2002—indicated the Al-Kibar facility was a copy of North Korea’s Yongbyon reactor, which had helped produce weapons-grade plutonium for the North’s nuclear-weapons program.

The U.S. intelligence community ultimately concluded with “high confidence” that Al-Kibar facility was a plutonium reactor, but, in the absence of evidence showing a reprocessing facility to produce fuel for a nuclear weapon, assessed with only low confidence that it was part of a weapons program. President George W. Bush opted against a U.S. strike and let the Israelis act by themselves, citing the lack of concrete intelligence.

After the strike, U.S. intelligence picked up signs that the Syrian government “went to great lengths to clean up the site and destroy evidence of what was really there,” according to a 2008 classified State Department cable written by Secretary of State Condoleezza Rice and later released by WikiLeaks.

The International Atomic Energy Agency assessed in 2011 that “the destroyed building was very likely a nuclear reactor” and chastised the Syrian government for failing to disclose information about Al-Kibar.

In his post-presidency memoir, former President Bush wrote that he had urged Prime Minister Ehud Olmert to reveal more about the strike on Al-Kibar and the intelligence that led up to it to isolate the Assad regime, but that Olmert preferred “total secrecy” because he felt publicity “might back Syria into a corner and force Assad to retaliate.”

Israeli authorities evidently no longer feel constrained by such concerns. The strike has long since faded from the top of Israeli-Syrian tensions, replaced by mounting tensions between the two countries following a series of reported Israeli airstrikes against alleged Assad regime weapons transfers to the Lebanese terrorist group Hezbollah and clashes along the border in the Golan Heights.

It’s unclear why Israel chose this particular time to declassify the operation against Al-Kibar, but politicians have already pointed to the strike as a warning to Iran not to develop nuclear weapons. Israeli Intelligence Minister Yisrael Katz tweeted Wednesday that the Al-Kibar incident shows “Israel will never allow nuclear weapons to countries like Iran who threaten its existence.”

Defense Minister Avigdor Lieberman echoed the sentiment in a statement, saying that Israel’s military and intelligence capabilities had only improved since the 2007 strike. "This equation should be taken into account by everyone in the Middle East," he said.