Irish twins Brooks Way will not perform on the inaugural X Factor live show due to "unforeseen circumstances", according to ITV.
The teenagers, Kyle and Josh Brooks, were due to perform as part of Louis Walsh's groups category alongside the other 11 acts in Saturday night's programme.
A spokesman said their performance was pulled due to a tip "given to the show regarding one of the group".
As the show opened, host Dermot O'Leary told viewers "due to unforeseen circumstances the Brooks brothers will not be performing this evening".
The pair, initially called The Brooks and who also appeared on the show before leaving at the judges' house stage in 2014, were included in the ITV programme's opening montage.
An ITV spokesman said: "As was said at the top of the show, due to circumstances that have arisen, Brooks Way won't be appearing tonight.
"This relates to information which has been given to the show today regarding one of the group."
First up to perform in the live show's were three-piece boy group Five After Midnight who performed an energetic rendition of Justin Timberlake's Can't Stop This Feeling which got judge Nicole Scherzinger off her seat.