Many former Iraqi officers, who once served under Saddam Hussein’s Baathist regime, are playing a “pervasive role” in the Islamic State (ISIS/ISIL) as “leaders” of the jihadist group, reports The Washington Post.

“Even with the influx of thousands of foreign fighters, almost all of the leaders of the Islamic State are former Iraqi officers, including the members of its shadowy military and security committees, and the majority of its emirs and princes, according to Iraqis, Syrians and analysts who study the group,” notes The Post.

“They have brought to the organization the military expertise and some of the agendas of the former Baathists, as well as the smuggling networks developed to avoid sanctions in the 1990s and which now facilitate the Islamic State’s illicit oil trading,” it adds.

Kurdish media outlet Rudaw reports that “a top ISIS leader who was once a general in Saddam Hussein’s army” was recently killed by a local militia in Fallujah, Iraq known as the Fallujah Liberation Committee.

The former Hussein-era general, Abu-Jihad Abdullah Dlemi, was described by the militia as “a top ISIS leader responsible for the group’s suicide bombings.”

A former ISIS fighter who grew disillusioned with the jihadist organization told The Post that local Syrian “emirs” are usually shadowed by Iraqi officials who make the important decisions.

“All the decision makers are Iraqi, and most of them are former Iraqi officers. The Iraqi officers are in command, and they make the tactics and the battle plans,” declared former ISIS member Abu Hamza. “But the Iraqis themselves don’t fight. They put the foreign fighters on the front lines.”

“His account, and those of others who have lived with or fought against the Islamic State over the past two years, underscore the pervasive role played by members of Iraq’s former Baathist army in an organization more typically associated with flamboyant foreign jihadists and the gruesome videos in which they star,” The Post explains.

ISIS leader Abu Bakr al-Baghdadi reportedly “embarked on an aggressive campaign” to recruit a number of Hussein Baathists who have now “become more than relevant” in the organization’s operations.

Among the Baathist military officials recruited by ISIS leader al-Baghdadi was Brig. Gen. Hassan Dulaimi, a former intelligence officer in the old Iraqi army who had been reportedly rehabilitated by the U.S. military.

The de-Baathification law enacted under L.­ Paul Bremer, Iraq’s American ruler in 2003, is described by The Post as a contributor to the rise of ISIS.

Under the law, 400,000 members of the defeated Hussein army were prohibited from serving in the government and denied pensions, but were also allowed to keep their guns.

Baghdadi’s recruitment effort were “further aided by a new round of de-Baathification launched after U.S. troops left in 2011 by then Prime Minister Nouri al-Maliki, who set about firing even those officers who had been rehabilitated by the U.S. military,” reports The Post.

“The crisis of ISIS didn’t happen by chance,” reportedly said former Iraqi intelligence officer Dulaimi. “It was the result of an accumulation of problems created by the Americans and the [Iraqi] government.”

After the U.S. withdrew from Iraq, ISIS “was the only surviving option” for former Hussein officers who had switched sides and aligned themselves with the U.S., Brian Fishman, who investigated ISIS in Iraq for West Point’s Combating Terrorism Center and is now a fellow with the New American Foundation, told The Post.

The article points out that much like the Hussein regime, ISIS has carried out beheadings and established branches in countries across the Middle East along with training camps for foreign fighters from across the Arab world.

Some question whether the Baathists adhere to ISIS’ Islamic extremist ideology.