Hong Kong’s leader ordered authorities to investigate after two dancers performing with Canto-pop boy band Mirror were struck by a giant video screen that crashed down onto the stage during the band’s performance at Hong Kong Coliseum in Hung Hom on Thursday night.

Police said the two male dancers were sent to Queen Elizabeth Hospital, and according to a Hospital Authority spokesman, one of the performers suffered neck injuries and was in serious condition in intensive care. The other dancer sustained injuries to his head and was listed as stable.

Three female audience members, ages 16, 21 and 40, were treated for shock, with one being sent to hospital.

The injured dancers are treated.

The concert was the band’s fourth of a planned 12 shows, but the government ordered the remainder to be suspended until the stage sets at the venue were checked and proved to be safe.

Chief Executive John Lee Ka-chiu said in a statement early on Friday he was shocked over the accident and ordered the Culture, Sports and Tourism Bureau, the Leisure and Cultural Services Department and related authorities to thoroughly investigate the accident and review the safety requirements of similar events to ensure the protection of performers, workers and audience members.

“I express sympathy to those who were injured and hope that they will recover soon,” Lee said.

MakerVille, the entertainment business arm of PCCW, and Music Nation – the concert organisers – apologised over the incident and promised to do everything they could to support the injured dancers.

Video clips circulating on social media show more than a dozen performers on stage dancing when one of a number of giant monitors comes loose from what appears to be suspension wires and slams onto the stage. At least one dancer was directly under the screen, which then fell backwards, footage showed.

The concert was immediately halted. Ahfa Wong Wai-kwan, Mirror’s manager, apologised and appealed to the audience to leave the coliseum in a calm fashion, according to a video circulated online.

“Thank you so much for your support to Mirror, but there is something that we need to handle now. I hope you can all leave in an orderly manner,” she said. “I’m sorry. I promise to settle your tickets and promise we will handle the show to ensure [everyone’s] safety.”

Audience members shouted in horror when the video screen plunged onto the stage.

“I was shocked,” said Aaron Chan Chun-tat, a 33-year-old lawyer who was seated in row 27 close to the stage. “Then everyone was evacuated.”

The scene inside Hong Kong Coliseum after the screen fell.

Another audience member, surnamed Chan, said she was “very traumatised” after seeing the screen fall, as she was sitting in the first few rows watching the stage when it happened.

“It happened too fast and it took everyone a few moments to realise what had happened. Everyone saw the dancers fall onto the floor, and we just hope they are OK,” she said.

Some concertgoers were swearing and cursing the stage design, while others were weeping.

Vince Leung, a former journalist who was attending the concert with a friend, said that in the moments before the incident, audience members were excited as Anson Lo Hon-ting and Edan Lui Cheuk-on were performing one of the band’s current hits, Elevator.

“It took a while for the audience to realise what had happened,” he said. “And then when we saw two dancers lying on the floor motionless with a big TV scene next to them, the coliseum suddenly went all quiet. Anson Lo and Edan Lui were quickly taken off the stage.

“The light on the stage was temporarily turned off, but then it turned on again after the audiences shouted together: ‘Turn on the light, Turn on the light’.”

One of the injured is treated by first responders.

Leung said that when she left the venue with her friend, she saw many fans still gathered around outside, wiping away tears.

“I am too shocked to go home now, so I do not know what to do,” she said. “ My heart is still racing. I need some time to calm down and process everything. I hope everyone will be fine, and whoever is behind the safety of the stage will be held responsible.”

Secretary for Culture, Sports and Tourism Kevin Yeung Yun-hung said authorities had contacted organisers on Wednesday after Mirror member Frankie Chan Sui-fai was injured when he accidentally stepped off the edge of an elevated stage. The bureau demanded a review of the conditions at the site and for improvements to be made to stage safety.

Engineering experts said Thursday’s accident was a rare occurrence in the coliseum’s 39-year history.

Structural engineer Ngai Hok-yan watched video clips of the incident and noted concert stage sets had to be approved by structural engineers. He questioned whether all the stage equipment had been properly installed.

At least two to four wires must be securely fastened to such large video screens, Ngai said. He suspected one of the locks might have failed, yet emphasised more evidence was needed before drawing any conclusions.

“This rarely happens at concerts, as a lot of testing would be done,” he said. “You can see the screen fall at a relatively slow pace and lean to one side, meaning the wires were pulled by a very strong force.”

The video screen that fell onto the stage.

Lawmakers Kenneth Fok Kai-kong and Priscilla Leung Mei-fun both called for a thorough investigation of the incident. Fok, whose responsibilities include performing arts and culture, said the concert series should be suspended until “safety is guaranteed”.

“I felt extremely shocked,” Leung said. “The organiser, the Leisure and Cultural Services Department and the Electrical and Mechanical Services Department are all responsible for ensuring the safety of the venue, so as to ensure all staff can perform under a safe environment.

“The authorities must investigate the cause of the accident, and whether it involves human negligence or poor supervision, to prevent the accident from happening again.”

Tickets for the concerts were priced at HK$480 (US$61) HK$880 and HK$1,280. The 12-member band, who are mostly in their 20s, shot to fame during the Covid-19 pandemic after winning ViuTV’s talent competition Good Night Show – King Maker in 2018.