‘Britain’s Got Talent’ viewers were busy on social media again last night, this time panning the live performance by Simon Cowell’s American girl group Fifth Harmony for being “flat, tuneless and boring” during Thursday night’s semi-final.

The five-piece group were formed in 2012 on the second season of ‘The X Factor USA’, and are currently the world’s highest-selling girl group, with a social media following of over three million and signed to ‘BGT’ judge Cowell’s Syco label.

They performed as special guests during the interlude between the judges picking the last finalists for this weekend’s season closer, with a rendition of their recent UK Top 10 hit ‘Work From Home’. However, Twitter users were quick to jump on them, criticising their stylisation, choreography and singing.

Fifth HarmonyFifth Harmony didn't go down well on 'BGT' on Thursday

“@BGT can you start using acts that are actually talented? #FifthHarmony what a vocal disaster!” one unhappy user wrote. “Fifth Harmony? More like no harmony,” another piled in, and the comments only got harsher from that point onwards.

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“I like Fifth Harmony but wth happened on BGT last night,” asked one confused follower, with another concurring: “Just watched #5HonBGT - didn't quite work, did it? #FifthHarmony #BGT”

“Fifth Harmony should really take a leaf out of Britney’s book and just lip sync,” one wrote. Another quipped: “Dear Fifth Harmony. You’ve gotta go to work, work, work, work, work, work, work on your live performances.”

Referencing the song's title, one BGT fan joked: “After their performance on @BGT I think @FifthHarmony should go ‘work’ on their vocals.” Ouch.

The group, comprising singers Ally Brooke, Camila Cabello, Dinah Jane, Lauren Jauregui and Normani Kordei, were formed having been runners-up on the 2012 edition of the American version of ‘The X Factor’, but have enjoyed massive success subsequently. They’re currently promoting their second album 7/27 and are due to kick off a world tour in Peru next month.

The final of ‘Britain’s Got Talent’ 2016 is on ITV at 7:30pm on Saturday (May 28th).

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