The stage's lighting scaffold and LED screen fell on to the stage at 00.40am at the Vessuwan Stadium's northern football field, while workers were installing equipment. Eleven were injured, three in a critical condition. One worker, Wichit Srichompoo, 35, later died of his injuries at Udon Thani Hospital.
The free concert's technical division head Chuchat Piriyawat said the workers were installing light, sound and additional systems on the stage when suddenly the aluminium structure and pillars collapsed. The stage was 22-metres-wide, 15-metres-deep and 13-metres-high.
Nakhon Udon Thani Municipality mayor Itthipon Triwattanasuwan said provincial engineers were inspecting the scene for the cause of the collapse. The concert organiser promised a press conference about the incident later.