Sept. 12, 2013 -- An American-born jihadist fighting for an al Qaeda affiliate in Somalia has allegedly been killed by the terror group, months after a public spat between the Alabama-raised man and the group's leadership.
Omar Hammami, known in the terrorist organization of al-Shabaab as Abu Mansoor al-Amriki and featured in a recent ABC News report, was gunned down in an al-Shabaab ambush in Somalia's southern Bay region, according to another member of the terror group cited in a report by The Associated Press. Agence France Presse reported similar circumstances for Hammami's alleged death, based on sources in the region.
Hammami has been reported dead several times before, but an African diplomat in the region and an American terrorism expert who has been in contact with Hammami told ABC News the reports are very likely true this time. Two senior U.S. officials said the American intelligence community is "cautiously optimistic" the reports are accurate, but they have not been confirmed.
Hammami is one of the highest-profile members of al-Shabaab and one of the most prominent accused American terrorists, with a $5 million reward from the State Department for information leading to his capture. He left the U.S. for Somalia in 2006 and rose in the ranks to eventually serve as a "military leader" in al-Shabaab, according to the U.S. government. He was indicted in the U.S. in November 2006 and charged with terrorism-related crimes.
"He's alleged to have made significant contributions to this terrorist organization's media and military activities," State Department spokesperson Marie Harf said today.
Hammami's father, Shafik, said today that he had been told of the reports but had no way to know if his son was actually dead.
"Of course I hope not, I hope it's not true," Shafik Hammami told ABC News in a telephone interview from his Alabama home. "Our lives have been on a roller coaster for a long time, and we've been there before... we just hope that it's not true this time."
If the reports are accurate, however, Shafik said his son died "fighting for his principles."
"He did what he wanted to do and he fulfilled his principles," Shafik said. "If he indeed died, he died fighting for his principles, whatever they are."
Hammami was sometimes referred to as the rapping jihadist after he produced several videos of him rhyming about waging war on the West and the glory of martyrdom.
Hammami's mother, Debra, told ABC News last May that she didn't "agree with the ideology of any of that."
"But I do love my son and I do have motherly love," she said then. "If I could just touch him for five minutes, I would be thrilled."
Earlier this month Hammami reportedly renounced his membership in al-Shabaab and his ties to al Qaeda in an interview with Voice of America's Somalia Service.
"I'm openly not from Shabaab, I'm openly not from al Qaeda, but I'm definitely a terrorist," Hammami said, according to VOA's English-language website. VOA reported Hammami said he was in hiding from the al-Shabaab leadership, which was trying to kill him.
Hammami, who was active on Twitter, suddenly disappeared from the social networking site months ago, following what he said then were al-Shabaab assassination attempts. Hammami and the local al-Shabaab leadership had an oddly public falling out, culminating in Hammami posting videos online in which he said he feared for his life.
When he stopped tweeting, many observers speculated Hammami had been killed then, but American intelligence officials told ABC News in mid-August that Hammami was still alive.
Author and terror expert J.M. Berger, who has interacted with Hammami since he surfaced on Twitter this year and monitors Shabaab social networks, said that unlike past reports of his death, this time it seems likely to have happened.
"The evidence strongly points to this report being true compared to previous claims, which were weakly sourced. The sources in this case include people known to be close to Hammami," said Berger, a writer and analyst for IntelWire.
An African diplomat in the region told ABC News there is a "significant possibility" Hammami is dead, but final confirmation won't come without DNA tests.
A U.S. State Department official said the department is aware of the reports, but they are still "working to ascertain the facts."
A self-described representative for al-Shabaab have not immediately returned request for comment.
ABC News' Mike Levine contributed to this report.