After Monday’s show, concert-goers took to social media echoing Sombr’s concerns.
One said it “took a long time” for staff to realise people were passing out, while another called for more safety precautions.
Olivia, 17, who attended the gig, told the BBC the venue felt “unprepared” and said the show had already been stopped earlier in the evening after another audience member passed out.
“It was so hot inside, there was just no air conditioning. I was genuinely boiling,” she said.
Olivia said she was near the front, where staff at the venue were handing out water, but she added it “wasn’t getting to the crowd in the back”.