At least 10 people were killed and dozens injured when a truck drove into a large crowd on Bourbon Street in New Orleans' French Quarter early on Wednesday, a city government agency said.
It said no further information was immediately available.
Earlier CBS News, citing witnesses, reported that a truck had crashed into the crowd at high speed, and then the driver got out and started firing a weapon, with police returning fire.
"Initial reports show a car may have plowed into a group of people. Injuries are unknown but there are reported fatalities," a New Orleans Police Department spokesperson told CBS News.
Emergency services transported dozens of injured people from the scene.
The area, a popular tourist destination, was crowded during early New Year's Day celebrations when the incident occurred.
The New Orleans Police Department confirmed they were investigating a mass casualty incident.
