Months before the man behind the New Orleans terror attack plowed a truck into a New Year’s Day crowd, he rode through the area on a bicycle, recording videos of his target using eyeglasses with a built-in camera, investigators said on Sunday. He was back again a few weeks later, they said, probably to continue his plotting.

Those details emerged as investigators revealed more about the driver and the extensive planning behind the attack, which killed 14 people, injured many others and left New Orleans starting 2025 grappling with a cascade of anguish and alarm.

Investigators have been pushing to piece together a clear timeline of the attacker’s actions. The investigation has entailed establishing a beat-by-beat accounting of his movements in the hours immediately before the attack, which included loading guns in his rented pickup truck and planting explosive devices in coolers near the site of the attack, Bourbon Street in the city’s French Quarter.

A far more sprawling search is looking back years to try to understand how a 42-year-old Army veteran with a lucrative job at an international accounting firm came to be radicalized, claiming alignment with the Islamic State terrorist group, better known as ISIS.

Investigators found that the attacker, Shamsud-Din Jabbar, had made trips to Egypt and Canada in 2023. But they said on Sunday that they had yet to determine what role, if any, those travels might have played in his evolving beliefs or his planning for the New Orleans attack.

“Our agents are getting answers as to where he went, who he met with and how those trips may or may not tie into his actions here in our city,” Lyonel Myrthil, the special agent in charge for the F.B.I. in New Orleans, said at a news conference.