The Hard Rock Hotel partially collapsed onto Canal Street downtown New Orleans, Louisiana. (AFP)

One person died and at least 18 others were injured Saturday when the top floors of a New Orleans hotel that was under construction collapsed, officials said.

The New Orleans fire department received reports at 9:12am local time that the Hard Rock Hotel in downtown New Orleans had collapsed.

One person died at the scene, according to Fire Chief Timothy McConnell, who added that the building is now structurally unstable.

"Another collapse is possible," he told reporters at the construction site.

Firefighters evacuated construction workers inside the hotel after the "upper six to eight" floors collapsed, McConnell said.

Emergency medical services director Emily Nichols said that first responders evaluated 19 people at the scene, 18 of whom were transported to hospitals and are in stable condition.

The last person refused transport.

Three people are still missing, and there are no reports of injury to passers-by.

Due to the hotel's unstable structure, the operation to clear the area is ongoing, according to local Homeland Security office director Collin Arnold.

He asked that people stay away from the area and refrain from using drones for either personal or media purposes to view the damage.

The fire department is working to evacuate nearby buildings, particularly apartment complexes.