The Ultra Music Festival opened at Bayfront Park in downtown Miami after a row of LED video screens collapsed onto the main stage, injuring three people.
Two men were trapped underneath the debris when the stage collapsed about 7:50 p.m. Thursday, according to Miami Fire Rescue Lt. Ignatius Carroll.
The two men were transported in critical condition to Jackson's Ryder Trauma Center, where they've since stabilized.
"It looks like their prognosis is going to be pretty good," added Carroll.
A third person sustained minor injuries. One of the victims, Joseph Green, is listed in stable condition. Two others were released.
It's unclear what caused the accident. Carroll said inspectors checked all six stages at Bayfront Park before the music festival began Friday. The opening of the festival was pushed back one hour because of the accident.
"It's not about, 'Well, the show must go on.' It's all about making sure they don't have anyone else getting hurt," said Carroll.
"I'm a little worried but I'm sure they'll get it figured out before they let anyone in," said Max Flynn, who flew in from Colorado to attend.
Ultra Music Festival runs through Sunday. It will also be held next weekend.