The terrorist who crashed a truck into crowds in New Orleans was probably acting alone, according to the FBI.
Authorities had initially feared Shamsud-Din Jabbar was working with others when he drove a truck, adorned with an ISIS flag, into New Year's revellers on Bourbon Street.
But on Thursday morning, local time, FBI deputy assistant director for counterterrorism Christopher Raia said: "We do not assess at this point that anyone else is involved in this attack."
Mr Raia said Jabbar was "100 per cent inspired by ISIS".
"We're digging through more of the social media, more interviews, working with some of our other partners to ascertain a little bit more about that connection," Mr Raia said.
Authorities have also clarified that 14 people were killed in the truck attack. The earlier reported death toll of 15 included Jabbar, who was killed by police during a shootout at the scene. At least 30 others were injured.
The FBI believes Jabbar rented the truck on December 30 in his home city of Houston, Texas, Mr Raia said.
He then drove to New Orleans on New Year's Eve.
Just before the attack, he posted five videos to Facebook.
"In the first video, Jabbar explains he originally planned to harm his family and friends, but was concerned the news headlines would not focus on the, quote, 'War between the believers and the disbelievers,'" Mr Raia said.
"Additionally, he stated he had joined ISIS before this summer."
CCTV captured Jabbar placing two improvised explosive devices (IEDs), which were hidden inside ice coolers, in the Bourbon Street area. They were later found and made safe. A detonator, apparently to blow up the IEDs, was found in the truck.
Jabbar was a US citizen and spent years in the army, including on deployment in Afghanistan in 2009.
'No definitive link' with Las Vegas explosion
Mr Raia said investigators had found no links between the attack and a truck explosion outside the Trump International Hotel in Las Vegas later on New Year's Day.
A Tesla Cybertruck containing explosives blew up at the hotel's entrance, injuring seven bystanders.
A man who died inside the truck, in an apparent suicide, was also a US Army veteran who had served in Afghanistan. The trucks in both incidents had been rented using the vehicle-sharing app Turo.
"We are following up on all potential leads and not ruling everything out," Mr Raia said.
"However, at this point, there is no definitive link between the attack here in New Orleans and the one in Las Vegas."
Since the New Orleans attack, president-elect Donald Trump has used social media to attack President Joe Biden, the Democratic Party, and authorities including the Department of Justice (DOJ) and FBI, as "incompetent and corrupt".
"With the Biden 'Open Border's [sic] Policy' I said, many times during Rallies, and elsewhere, that Radical Islamic Terrorism, and other forms of violent crime, will become so bad in America that it will become hard to even imagine or believe," Trump posted. "That time has come, only worse than ever imagined."
The FBI says Jabbar was born in the US.
His home in Houston and a property in New Orleans were searched after the attack.
Mr Raia said three phones and two laptops had been seized.
More than 400 public tips had also been received, he said.
New Orleans swept for bombs
Bourbon Street, a popular tourist strip and party zone, reopened on Thursday afternoon as the city prepared to host the Sugar Bowl college football game.
The annual event was scheduled for New Year's Day, but was postponed for 24 hours.
In a video broadcast before the game, Mr Biden said: "I'm glad the game is back on for today. But I'm not surprised, because the spirit of New Orleans can never be kept down. That's also true of the spirit of America."
Ahead of the game, travellers who had come to see it told the ABC they were confident it would be safe.
"I've prayed over the stadium," said Jodi Lozano, who was visiting from Texas.
"I've seen cops and authorities everywhere and they're doing such a great job to protect us and to sweep the city and make sure that we're OK. So I'm feeling pretty good about it."
Her friend, Paige Echols from Atlanta, also praised authorities' efforts to secure the city.
"I think that a lot of people are upset about the fact that they postponed the game, but I think it was the right thing to do, just to make sure that they've gotten the streets cleaned out, they've gotten the Superdome checked over again."
Bomb-detection dogs have swept the area. They will stay in the city in the lead-up to mardi gras celebrations, which start next week, and February's NFL Super Bowl, local authorities said.
Bars and restaurants in the tourist hotspot have reopened their doors, and live music is being played in Bourbon Street.
But there's still a visible police presence on the street and the surrounding area.
Gail Morris, who travelled to New Orleans from Texas for New Year's celebrations, was among the tourists who returned to the French Quarter after the area reopened.
"We didn't even know if it would be reopened or not. We're leaving tonight to go back to Houston, but we just thought we'd walk over and see," she said.
"I felt my heart hurting when I walked that first block."
Ms Morris had been on nearby Decatur Street on the night of the attack.
"I was going to come here to Bourbon, and I was a little chilly and just a little bit tired from being out the night before, so I went back to my hotel. So I was fortunate that I didn't come here," she said.
