Two workers were taken to Jackson Memorial Hospital’s Ryder Trauma Center in Miami yesterday after a section of LED screen fell from the main stage as final preparations were being made for this weekend’s popular Ultra Music Festival in Downtown Miami. CBS Miami reports that two are in serious condition while another is stable and a fourth worker was checked and released at the scene.

The accident occurred last night as a large section of LED screen was being hoisted up, falling from as high as 30 feet.

Ultra organizers released a statement last night indicating investigations are underway.

“Today (Thursday, March 14) as preparations were being made for this weekend’s Ultra Music Festival, a section of an LED screen fell and injured two workers. Fire Rescue was on site so there was a rapid response. Festival organizers are working with, and supporting, authorities as they investigate the details behind the accident.”

It is unclear at this time if the music festival will continue as scheduled or be delayed.

Ultra Music Festival is scheduled to take place over the next two weekends and feature major acts such as David Guetta, Swedish House Mafia, Deadmau5, Avicii and Snoop Lion.

Head to CBS Miami for complete coverage.