11 people have been injured in a gun attack in New Orleans’ French Quarter, but several hours after the early morning shooting, key details including a motive remains unclear.

Two are in a critical condition, and a ‘person of interest’ has been detained according to police superintendent Shaun Ferguson.

Of the critically injured, one was shot in the chest, and the other in the torso.

It happened in the early hours of Sunday, and the victims were taken to two different hospitals. Additional details on their conditions have not been released.

The shooting happened on the busy commercial 700 block of Canal Street, close to many hotels.

Officers responded quickly, according to police, because patrols had been heightened for the annual Thanksgiving weekend rivalry football game between Grambling State and Southern University at the Superdome.

Police initially thought they were being fired upon when they heard shots.

One witness, Kenneth Culbreth, told NOLA.com that he leaving a pharmacy when he heard gunfire. "I heard pops. It was so many, I couldn't keep count."

A woman looks out from inside a McDonald's fast food restaurant as New Orleans police investigate the scene of the shooting (AP)

An employee at the pharmacy said: "I heard three rounds, and people started running."

It's the second major shooting to happen in three years on the weekend of the football game, known as the Bayou Classic.

A fingertip search of the area was carried out on Sunday morning

In 2016, two men got into an argument that turned into a shootout, injuring nine people and killing one.

New Orleans police are also investigating a shooting in a different part of the city that killed two men and wounded two others, which happened several hours after the Canal Street shooting.