“The FBI is working to determine the subject’s potential associations and affiliations with terrorist organisations,” the agency said in a statement.
US President Joe Biden, describing the attack as “despicable”, said hours beforehand, Jabbar had posted videos online “indicating that he was inspired by Isis”.
Officials said a manhunt was under way, with FBI agent Alethea Duncan warning that authorities “do not believe that Jabbar was solely responsible”.
“We’re hunting some bad people down,” Louisiana governor Jeff Landry said.
An FBI spokesman told AFP 15 people had been killed, citing the New Orleans coroner’s office.
Aiming for ‘carnage’
Police said the incident began around 3.15am (local time) in the heart of the French Quarter, which was packed with people celebrating the start of 2025.
The suspect drove a white Ford F-150 electric pick-up into a group of pedestrians, then exited and was killed in a shoutout with police officers – two of whom were wounded. Two home-made bombs were found and neutralised, the FBI said.
“This man was trying to run over as many people as he possibly could,” Kirkpatrick told reporters.
Driving at “very high speed” and in a “very intentional” manner, “he was hellbent on creating the carnage and the damage that he did”, Kirkpatrick said.
The wounded officers were in stable conditions and Kirkpatrick said they would recover.
The Pentagon said Jabbar had served in the army as a human resources 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.
Biden said that law enforcement were also probing any possible links between the attack and the explosion of a Tesla Cybertruck outside a hotel partly owned by US President-elect Donald Trump in Las Vegas that killed one person.
“Thus far, there’s nothing to report on that score,” he said, as police in Las Vegas said they believed it was an “isolated” incident.
Trump immediately linked the New Orleans attack to illegal immigration, giving no evidence, in a statement made before authorities announced the suspect was American.
Horror in iconic neighbourhood
In the wee hours of the year’s first day, revellers were celebrating in the French Quarter, a district renowned for its bars, restaurants, jazz history and Mardi Gras parties.
Bystander Zion Parsons said he saw that instantly turn into a scene of horror.
“The best way I can describe it is: Truly a warzone,” he told CNN. “There were bodies and blood and all the trash.”
“People were terrified, running, screaming,” he said.
Another witness, Jimmy Cothran, told ABC the mayhem was “insanity”.
“We instantly counted, I’d say, 10 bodies – six clearly graphically deceased, and the others yelling with no one around,” he said.
New Orleans is one of the most-visited destinations in the United States and on February 9 will stage the NFL’s Super Bowl game – one of the biggest sporting events of the year.
The attack came just hours before the city was due to host the Sugar Bowl, a major college football game. That game was delayed until Thursday, officials said.
Policing had already been heavy over the New Year’s holiday, according to the city, as authorities braced for big crowds.