The New Orleans attack suspect, identified by the FBI as 42-year-old US citizen Shamsud-Din Jabbar, appeared to be a real estate agent from Texas who served for years in the military but experienced financial difficulties and divorce.
In a video posted on YouTube four years ago, Jabbar -- speaking with a southern US accent -- boasted of his skills as a "fierce negotiator" as he advertised his property management services to potential clients.
The Pentagon said Jabbar had served in the army as a human resource specialist and an IT specialist from 2007 to 2015, and then in the army reserve until 2020.
He deployed to Afghanistan from February 2009 until January 2010, an army spokesperson said, adding that he held the rank of Staff Sergeant at the end of his service. Earlier the FBI had said it believed he was honorably discharged.
Criminal records reported by The New York Times show that Jabbar had two previous charges for minor offenses -- one in 2002 for theft and another in 2005 for driving with an invalid license.
Jabbar was twice-married, according to the newspaper, with his second marriage ending in divorce in 2022, when he detailed experiencing financial problems in an email to his wife's lawyer.
"I cannot afford the house payment," he reportedly wrote, adding that his real estate company had lost more than $28,000 in the previous year, and that he had taken on thousands in credit card debt to pay for lawyers.
A man named Abdur Jabbar, in Beaumont, Texas, told The New York Times he was the suspect's brother and described him as "a sweetheart really, a nice guy, a friend, really smart, caring."
He said the suspect had converted to Islam at a young age, but that "what he did does not represent Islam. This is more some type of radicalization, not religion."
President Joe Biden told reporters that, hours before the attack, Jabbar shared videos online that indicated he was "inspired by ISIS," citing information from detectives and using another name for the Islamic State armed group.
A black flag linked to the group was also found in the vehicle used in the attack, the FBI said.
Georgia State University confirmed to AFP that a person named Shamsud-Din Jabbar attended the university from 2015-2017, graduating with a bachelor's degree in computer systems.
In his YouTube video -- seen by AFP but later removed by moderators -- Jabbar spoke highly about his time serving in the US military.
He said that with this experience, he "learned the meaning of great service and what it means to be responsive and take everything seriously, dotting I's and crossing T's to make sure that things go off without a hitch."
At least 15 people were killed and dozens wounded when Jabbar allegedly drove a truck at high speed into a crowd of New Year's revelers in New Orleans.
Authorities said he crashed the vehicle, then opened fire and was killed in a shootout with police.
