The Islamic State leader killed Thursday during a U.S. Special Operations forces raid in Syria was working undercover trying to rebuild the terrorist group, carried a gun wherever he went and once was detained by American forces in Iraq nearly 15 years ago, reports say. 

Abu Ibrahim al-Hashimi al-Qurayshi, who assumed control of the militant group in October 2019 following another U.S. military raid that killed former leader Abu Bakr al-Baghdadi, detonated a large amount of explosives during the overnight operation in Atmeh, sources told Fox News

"Several Iraqi intelligence officials say al-Baghdadi kept [Al-Qurayshi] away from the battlefield with the intention of protecting him so he would lead ISIS in the future, particularly because of his academic study of Islam, his two-decade history as part of jihadist groups, and his detailed, firsthand knowledge of the organization’s structure," BBC correspondent Feras Kilani wrote last year about the shadowy militant leader. 

A poster advertising a $10 million U.S. reward for information about Abu Ibrahim al-Hashimi al-Qurayshi, who also went by the name Amir Muhammad Sa’id Abdal-Rahma al-Mawla.

ISIS LEADER KILLED IN US SPECIAL OPERATIONS RAID IN SYRIA, BIDEN SAYS 

In Kilani’s report for BBC Arabic, translated into English for New Lines Magazine, he cited a former ISIS detainee and Iraqi intelligence sources as saying that Al-Qurayshi carried a firearm wherever he went and as of 2021, was working undercover in Syria with the intent of rebuilding ISIS. 

The report also says U.S. forces once arrested Al-Qurayshi after raiding his home in Mosul, Iraq, in 2008. He then was held and interrogated at the Camp Bucca U.S.-run detention center before being released in under unclear circumstances, the report added. 

In 2020, the U.S. State Department’s Rewards for Justice Program announced that it was doubling its award to $10 million for information leading to the identification or location of Al-Qurayshi, who also went by the name Amir Muhammad Sa’id Abdal-Rahma al-Mawla, as well as several other aliases.

Abu Ibrahim al-Hashimi al-Qurayshi steadily rose through the ranks of ISIS, the State Department says. (US State Department/Universal History Archive/Universal Images Group via Getty Images/ Photo illustration)

"Al-Mawla helped drive and justify the abduction, slaughter, and trafficking of members of Yazidi religious minority groups in northwest Iraq, and he oversees the group’s global operations," the State Department said at the time.  

"Born in Mosul, Iraq, in 1976, al-Mawla was a religious scholar in ISIS’s predecessor organization, al-Qae da in Iraq, and steadily rose through the ranks of ISIS to become the deputy emir," it added. 

During his time as ISIS’ leader, Al-Qurayshi also kept a low profile, the Associated Press reports, citing the nonprofit Wilson Center. 

People check at a destroyed house after an operation by the U.S. military in the Syrian village of Atmeh, in Idlib province, Syria, on Thursday. (AP Photo/Ghaith Alsayed)

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"Al-Mawla has not even given an audio address in which Islamic State members might hear his voice -- a sharp break in precedent," a December 2021 document by the Wilson Center reportedly said. "Some disaffected former members of the group have argued that it is contrary to the Sharia to pledge allegiance to a ghost, but that does not seem to have swayed opinion. If there was opposition to al Mawla’s ascension, it has not manifested on the battlefield." 

With Abu Ibrahim al-Hashimi al-Qurayshi now out of the picture, it is unclear who will become the next leader of the embattled terrorist group.