S Club fans were plunged into darkness after reports of a fire at the pop group's concert in Liverpool on Monday.
The Never Had A Dream Come True hit-makers had already been forced to reschedule the date after another reported fire.
People attending the gig at the M&S Bank Arena on October 30 were evacuated after the lights went out just before 9pm.
The original concert had been due to take place on October 13.
Angry fans took to X to vent over the latest setback in seeing their idols live.
"Seeing S Club 7. there was a fire and we got evacuated," penned one person on the micro-blogging site.
"Another fire at the #MandSBankArena in Liverpool. S Club aren't having the best of luck with this arena," lamented another.
In a statement, the M&S Bank Arena said: "Tonight, as S Club were close to finishing their set at the arena, there was a minor incident which triggered a partial evacuation.
"The issue was resolved quickly and we were able to restart the show.
"We will be launching a full investigation. The safety of the audience, staff and performers is always our primary concern."
S Club first announced plans to reform earlier this year for a UK tour to mark their 25th anniversary.
This appeared to be thrown into jeopardy a few months later when member Paul Cattermole died unexpectedly aged 46 from an underlying heart condition.
While remaining members Bradley McIntosh, Rachel Stevens, Jo O'Meara, Tina Barrett and Jon Lee vowed to carry on, Hannah Spearritt, who had previously been in a romantic relationship with Cattermole, pulled out, leaving just five of the original seven line-up.
