TEHRAN (Press Shia) – After more than a decade of secrecy, the Zionist regime of Israel confirmed it has conducted a 2007 military raid on what was believed to be a Syrian nuclear reactor.

The Israeli army said a total of eight F-16 and F-15 fighter jets bombed a Syrian nuclear facility in Deir ez-Zor, 450km north of Damascus, in a stealth operation that lasted four hours overnight on September 5 to 6, 2007.

The attack, dubbed "Out of the Box" by Israel's military command, was long known to have occurred but was kept under an 11-year gag order forbidding Israeli media to publish details on the operation, Al Jazeera reported.

"The message from the attack on the nuclear reactor in 2007 is that the state of Israel will not allow the establishment of capabilities that threaten Israel's existence," said Israeli army chief of staff Gadi Eizenkot.

"This was our message in 2007, this remains our message today and will continue to be our message in the near and distant future," he added.

In 2011, the head of the International Atomic Energy Agency (IAEA), Yukia Amano, said for the first time that the target destroyed by Israeli warplanes was the covert site of a future nuclear reactor.

Amano's comments countered assertions by Syria that it had no atomic secrets, and it was the first time the UN nuclear watchdog spoke unequivocally about the issue.

"The facility that was … destroyed by Israel was a nuclear reactor under construction," Amano said.

Previous reports by the IAEA only suggested that the structure could have been a nuclear reactor. In a February report, Amano said that features of the bombed structure in al-Kibar were "similar to what may be found at nuclear reactor sites".