U.S. intelligence officials are scrambling to confirm reports that Omar Hammami, the American-born leader of an Al Qaeda-aligned terror group in Somalia, has been executed. 

Unconfirmed reports surfaced in Somali media claiming the al-Shabaab jihadist was hunted down and beheaded on orders from a rival leader in the network.   

A U.S. intelligence official told Fox News that, if true, Hammami's death could be a turning point in the recruitment of Americans and western Europeans by al-Shabaab -- as Hammami was thought to play a prominent role in that western outreach. 

"Our folks have been looking for anything on this," the intelligence official told Fox News, adding: "We have not been able to confirm this report." 

Significantly, web postings on jihadist forums have surfaced that speak of the American's death. 

Somali media reports claim Shabaab leader Ahmed Abdi Godane is accused of ordering the execution. Hammami reportedly said last month in a statement that other Shabaab leaders had him fearing for his life. 

Hammami, born in 1984, grew up outside Mobile, Ala., in the city of Daphne. 

But the American has been in war-torn Somalia for several years. In that time, he has emerged as one of the most recognizable and outspoken voices of terrorist propaganda. He was going by the name of Abu Mansour al-Amriki, or "The American." 

Al-Amriki first surfaced in the terror group in October 2007, when Al-Jazeera TV aired a report about the "common goal" of Al Qaeda and hard-line militants in Somalia. The report described al-Amriki as "a fighter" and "military instructor," but he concealed his face with a cloth wrap throughout the report. 

In April, he showed his face for the first time, during a highly-polished, 30-minute recruitment video posted online. It featured anti-American hip-hop music and sporadic images of Usama bin Laden. 

Hammani's death could be a blow to the Al Qaeda affiliate, at least for its western recruiting efforts. 

Al-Shabaab was responsible for the recruitment of some two dozen young men of Somali descent from the Minneapolis area.