A combination photo shows two of the al-Qaeda operatives released: Saif al-Adel, left, and Abdullah Ahmed Abdullah. (FBI)

The Iranian government has released a number of top al-Qaeda operatives that it has held for years in exchange for one of the country’s diplomats who was kidnapped in Yemen, U.S. officials confirmed.

The release could provide an immediate boost to al-Qaeda, whose leadership has been significantly degraded by a CIA drone campaign.

The development was first reported this week by Britain’s Sky News, which said the men were released this year in exchange for the Iranian diplomat. He was reportedly abducted in Sanaa, ­Yemen’s capital, in 2013.

Officials said it’s unclear whether the men were released in Yemen or another al-Qaeda stronghold, possibly in Syria or the tribal areas of Pakistan.

Among those freed were two key Egyptians, Saif al-Adel, the group’s chief of military operations, and Abu Kayr al Masri, who once ran al-Qaeda’s management council.

Either could potentially succeed the current al-Qaeda leader, Ayman al-Zawahiri, who is also Egyptian.

Another operative released was Abdullah Ahmed Abdullah, an Egyptian who worked closely with Adel. The former chief of training was the “most experienced and capable operational planner not in U.S. custody,” according to a top-secret 2008 U.S. document.

Adel and Abdullah were indicted in the 1998 bombings of U.S. embassies in Tanzania and Kenya that killed hundreds. The United States has offered $5 million for information leading to the capture of either man.

Also released, according to Sky News, was Khalid Mustafa al-
Aruri, 58, a.k.a. Abu Qassam, a Jordanian. He was once a top lieutenant to Abu Musab al-Zarqawi, the founder al-Qaeda in Iraq, the group that evolved into the Islamic State. Zarqawi, a Jordanian, died in a U.S. airstrike in 2006.

Aruri’s brother, a U.S. citizen, told the FBI that the al-Qaeda operative brought shame to his family, according to U.S. diplomatic cables disclosed by the anti-secrecy group WikiLeaks.

Sari Shihab, another Jordanian who was once close to Zarqawi, was also freed by the Iranians.

In the past several years, as many as a dozen senior al-Qaeda figures have left Iran. Two — Nazih Abdul-Hamed al-Ruqai, accused in the 1998 East Africa embassy bombings, and Sulaiman Abu Ghaith, Osama bin Laden’s son-in-law and former spokesman — have subsequently ended up in U.S. custody.

In July, the United States said it killed senior al-Qaeda operative Mushin al-Fadhli in a strike inside Syria. Once detained in Iran, Fadh­li led an al-Qaeda group sent to Syria by the group’s leadership to plan attacks against the West.

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