Officials added that investigators are reviewing a series of video recordings Jabbar made before the attack.
"He was driving a Ford pickup truck, which appears to have been rented, and we are working to confirm how the subject came into possession of the vehicle," the agency said, as it confirmed the presence of what appeared to be an Isis flag in the truck.
The FBI is leading the investigation, and during a press conference yesterday afternoon, it described the attack as an act of terrorism likely involving several suspects.
The attack occurred on the 100 block of Bourbon Street, which has been declared a crime scene and is off-limits until the FBI concludes its investigation after discovering two improvised explosive devices and more in the suspect's vehicle.
Law enforcement, with the help of bomb-detection dogs, has swept that area and others in New Orleans, including the Superdome football stadium, to ensure no other explosive devices have been deployed.
US Senator John Kennedy called the attack an example of "objective evil”.
"We expect to put the full force and resources of the federal government behind this investigation," Kennedy said at the press conference.
"When it is appropriate, you will find out what happened and who was responsible, or I will raise fresh hell and chase those in the federal government who are responsible until they tell us like they stole Christmas.”
The city was scheduled to host the Allstate Sugar Bowl NCAA football playoff game last night at the Superdome but postponed the contest for 24 hours.
New Orleans is one of the country's top tourist destinations during the holiday season, and the Sugar Bowl attracts thousands to the city annually. This year's game is part of the new NCAA football playoff format.
Louisiana Governor, Jeff Landry called the investigation a "very fluid process”.
"We're hunting some people down and getting the city ready for the Sugar Bowl tomorrow," he said.
Asked how he and others know the suspect did not act alone, Landry responded, "Why would we tell you that?"
He said answering that question might compromise the federal investigation in which state law enforcement is assisting.
The governor said he called up 100 military police officers to help secure the city and protect against other potential acts.
"We need more resources. We need more boots on the ground," Landry said. "We have an active investigation and we need to enhance our security."
Fifteen people were killed and dozens were injured in the incident at 3.15 am local time when a suspect slammed a pickup truck into pedestrians in the crowded and iconic French Quarter.
Officials said Jabbar was shot dead after he exited his vehicle and opened fire at police.
Three NOPD officers returned fire and killed Jabbar. Two of the officers were wounded in the exchange but are in stable condition.
The FBI said the flag of the Islamic State was found in the vehicle and that it is "working to determine the subject's potential associations and affiliations with terrorist organisations”.
"The FBI's special agent bomb technicians are working with our law enforcement partners to determine if any of these devices are viable, and they will work to render those devices safe," the agency said.
Police said Jabbar drove around established barricades and at a high rate of speed into the heart of the French Quarter at Bourbon and Canal streets.
Authorities said it appears that mostly locals were harmed in the incident, but some of the casualties included tourists.
Two Ochsner Health hospitals, treating those injured in the attack, are asking the public to donate blood.
"Our hearts go out to all those affected by the tragic event in the French Quarter during the early morning hours of Jan 1. To support those impacted, please consider donating blood," the health system urged in a statement, as it announced plans to hold blood drives through Thursday.
Thirty victims were taken to five different hospitals.
The White House said President Joe Biden called New Orleans Mayor LaToya Cantrell on Wednesday morning "to offer full federal support following the horrific news that a driver killed and injured dozens of individuals in New Orleans overnight."
The president has "been briefed on the latest developments by senior FBI and [Department of Homeland Security] leadership and his homeland security team, and he will continue to be briefed on this incident throughout the day," the official statement said.
"I am grateful for the brave and swift response of local law enforcement in preventing even greater death and injury," Biden said a separate statement. "I have directed my team to ensure every resource is available as federal, state, and local law enforcement work assiduously to get to the bottom of what happened as quickly as possible and to ensure that there is no remaining threat of any kind."
— Bernama-UPI
