New Orleans: The Texas field office for the FBI confirmed that they were executing a search in the suspected perpetrator's hometown of Houston.
"At this time, no arrests have been made, and FBI personnel will be at the scene for several more hours," the bureau wrote on X, adding that specialized units such as SWAT teams and bomb squads were also participating.
Investigators said they were also conducting simultaneous searches in New Orleans, Louisiana and "other states."
The 42-year-old suspect, Shamsud-Din Jabbar, is believed to have been a former IT specialist with the US army and a convert to Islam. A flag of the "Islamic State"(IS) terror group was found in his car.
The suspect died in a shootout with police after ramming a car into a crowdof New Years' revellers at about 3:15 am local time on January 1. Fifteen people were killed and dozens injured.
Chinese foreign affairs spokeswoman Mao Ning told repoters that Beijing was "shocked" by the "violent attack" in New Orleans.
"China always opposes any violent and terrorist acts targeting civilians," she said, adding: "We mourn the victims, and express our sympathy to their families and those injured."
World leaders such as France's Emmanuel Macron, the UK's Keir Starmer and Ukraine's Volodymyr Zelenskyy had earlier also expressed their sympathies over the incident.