(AhlulBayt News Agency) - The crowd was watching the Krewe of Endymion parade – one of the many parades to take place in New Orleans around Mardi Gras – in the mid-city section of New Orleans when the incident took place.
21 of the injured have been rushed to seven different hospitals across the area – including five who are in critical condition.
28 people in total were injured in the incident including a three-year-old child.
A female police officer, who witnesses claim was pinned under the truck, suffered non-life threatening injuries
Shortly after the incident Police spokeswoman Ambria Washington said: “Initial reports show so far about a dozen people are in critical condition.
"That number could increase as the investigation is ongoing."
New Orleans Mayor Mitch Landrieu has claimed the suspect was "drunk" at the time and has now been taken into custody.
The parade was just beginning to pass between Orleans Street and Carrolton Avenue at 0:45am GMT (6:45pm local time) when the pick-up truck drove into two cars before and plowing through the crowd, witnesses have claimed.
One of the cars is believed to have ricocheted off the truck and into pedestrians, causing further casualties.
The FBI are assisting investigations into the incident.
One onlooker said: “Word is the pickup truck plowed through crowd. Driver appeared drunk.”
“My heart breaks. People have been out here just wanting to see parade."
Police have said they do not believe the incident was an act of terror.
The parade is still continuing through the city despite scores of emergency vehicles attending the scene.
One witness said: “I actually literally felt it. I felt a rush it was so fast.”
Another, who claimed the driver seemed unaware of what he had done, said: "He was just kind of out of it."
It comes after a man was shot and wounded amid the festivites after a gun owner accidentally discharged their weapon from inside a portable toilet.
Some of the officers on duty across the parade were present for both incidents.
Mayor Mitch Landrieu said: "Obviously you don't want to have a day like this.
"We train year round to respond to events that can't be stopped because of bad decisions."
A police spokesperson added: "We tell people not to drunk drive. We tell them not to bring guns.
"We ask people to make good decisions."
Police Chief Michael Harrison said there was no indication that the accident was an act of terrorism.
The Endymion parade is one of the biggest parades in Louisiana and one of the most family-oriented ones. Many parents had brought their children to the event this year.
In a similar incident, dozens of people were killed and injured after a truck drove into a Christmas market in the German capital Berlin in December 2016.