One person was pronounced dead at the site, a fire official said during a news conference.
"This remains a very fluid and very unsafe situation, and every few minutes something is falling off this building", said Louisiana Governor John Bel Edwards during the press conference.
Another hanging crane is said to be unstable at the moment, and more of the building could collapse - so police and the fire department have cleared neighboring streets and evacuated surrounding buildings.
He confirmed that one person died and at least three people are still missing.
So far, Acadian Ambulance, who is providing aid to New Orleans EMS, has reported 13 patients transported for treatment and according to WWL-TV, it is believed there are still people trapped inside.
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McConnell told reporters that it's still a very risky situation and another collapse is possible.
It's unclear what exactly caused the building to cave - doesn't sound like the construction site was all that safe to begin with.
"It's still a very risky situation", he said.
The building collapse was caught in a dramatic video.
Construction plans for the 350-room hotel include a 12,000 square foot event space, two ballrooms and a residential space, according to a news release. Another building on Canal Street was destroyed by a fire three years ago.
"It looked like the concrete just slid from the top all the way down to the street", Worges said.