Four people were injured, two critically, after a LED display that hung from a stage fell at the site of the Ultra Music Festival Thursday night, Miami Fire-Rescue said.

Two workers were trapped after the lighting display fell in Bayfront Park, while debris hit another person, Miami Fire-Rescue spokesman Lt. Ignatius Carroll said.

Firefighters were able to free the trapped people and rushed them to Jackson Memorial Hospital's Ryder Trauma Center, Carroll said.

Ultra Music Festival Road Changes

Early Friday, the workers were upgraded from critical to stable condition, Carroll said.

He said the LED display crashed at about 7:50 p.m. on the stage at the south end of the park. It is one of two main stages for the festival, which is scheduled to begin Friday.

Carroll said Friday afternoon that Ultra organizers have been given permission to remove debris and prepare the stage.

Organizers said the festival was 99 percent sold out, but some tickets would be available on site.

Inspectors returned to the park Friday to check the main stage and make sure it's safe, Carroll said. They were also inspecting the other six stages where festival events will take place.

"We're gonna go inside, look at the main stage, see if we can try to determine why those light panels came crashing down," Carroll said.

Festival organizers said Friday they were working with inspectors.

"Following last night's incident, event organizers are on the ground working tirelessly with the Fire Department, OSHA and other regulatory authorities to ensure the festival site is absolutely safe for all festival-goers and crew," their statement read. "Ultra maintains its long-standing commitment to ensuring safety for its festival-goers and continues its preparations to open today."

With the party about to get underway, festivalgoers said they were not overly concerned about Thursday night's accident.

"I was a little worried but things happen like that all the time, I'm sure it'll be fine," Hunter Garroway said.

Byron Halland, who came from Colorado for Ultra, agreed.

"As long as it's back up and it's safe this time, shouldn't be a problem, and the people that got injured are in our prayers for sure," he said.

Ultra Music Festival Expanding to 2 Weekends

One witness described the display as an approximately 30-foot-long rectangular video monitor that was suspended under the red “U” above the stage.

Authorities had initially reported that a stage collapsed.



Construction was almost complete on the stage where the incident occurred, but all operations were halted there Thursday night.

“And right now we’re going to suspend any of the building on that stage until daylight, where we can be out here with structural engineers, OSHA as well, and then the fire marshal’s staff, to make sure that this stage and all the other stages are going to be safe for the Ultra Fest," Carroll said.

One person who was injured refused treatment on the scene, Capt. Bill Christopher, a dispatcher with Miami Fire-Rescue, told NBC News.

PHOTOS: An Ultra Weekend

The 2013 festival is due to begin Friday, with its first weekend running through Sunday, to be followed by a second weekend Friday, March 22 through Sunday, March 24.

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