This combination of pictures created on March 20, 2018 of handout images provided by the Israeli army reportedly shows an aerial view of a suspected Syrian nuclear reactor during bombardment in 2007. (AFP photo)

JERUSALEM, March 21 (Xinhua) -- The Israeli military Wednesday acknowledged Israel's involvement in airstrikes that demolished a suspected nuclear facility in Syria 11 years ago.

Israel has never previously admitted it was involved in the strikes on the Deir ez-Zor facility, 450 km northeast of Damascus. On Wednesday, the Israeli censor's office lifted a long-held prohibition on publishing information on the attack.

In a statement, the military said in the assault, dubbed "Operation Out of the Box" by the army, Israeli fighter jets attacked and destroyed an undeclared nuclear facility in Deir ez-Zor on Sept. 6, 2007.

The facility was in the advanced stages of construction, posing a possible threat to Israel, according to the statement.

Several months after the strike, the United States announced that intelligence indicated the site was a nuclear reactor with military purpose, although Syria denied it.

The attack was a result of an extensive intelligence effort. The collection of information began in 2004 and included cooperation with "parallel security forces," the statement said, hinting at top-level coordination between the Israeli government led by former Prime Minister Ehud Olmert and the George W. Bush administration ahead of the strike.

Commenting on the operation, the then Chief of Staff Gabi Ashkenazi said the army feared the strike would spark a war in the region and took steps to prevent an escalation as part of the preparations for the operation.

Israel's Chief of Staff Gadi Eizenkot, who served as commander of the Northern Command during the operation, said: "The lesson from the 2007 attack on the reactor is that the State of Israel will not accept the establishment of a capability that constitutes an existential threat to Israel. This is the message to our enemies in the near and far future."

The issue has recently resurfaced after Olmert compiled a memoir during his time in prison, where he served a 16-month corruption sentence. The manuscript, which includes a chapter about the attack and Olmert's part in leading to the decision to execute it, was sent for review to the censor's office.