X Factor's Stereo Kick's interrupted by stage invader

Stereo Kicks almost became a nine-piece band last night when their X Factor performance was gate crashed by comedian Lee Nelson.

The band, who are mentored by Louis Walsh, managed to keep their composure as a member of the audience ran onto the stage during their rendition of Michael Jackson's hit, You Are Not Alone.

The stage invader, who was dressed in a bright red bomber jacket, turned out to be Simon Brodkin. Brodkin is better known as comedian Lee Nelson who stars in the BBC Two comedy series of the same name. 

Despite the interruption Stereo Kicks put on an impressive performance and were praised by the judges.

Mel B said: "This is what I wanted you to bring to the stage from day one. Your harmonies were great and you dealt with a stage imposter, it was perfect."

Cheryl Fernandez-Versini conitnued: "I don’t know how I would have dealt with what you just dealt with. Very professional, congratulations for that."

Simon Cowell added: "Good for you for keeping going, these things happen on live TV. You bounced back from last week. I hope the public keep you in."

Louis Walsh joked: "Everyone wants to be in this band now - someone just walked out of the audience onto the stage!"

Minutes after he was escorted from the stage by security Nelson tweeted confirmation that he was the invader. He wrote: "There are so many of them I thought anyone could have a go. Really hope the boys keep me on #LeeNelsonForStereoKicks

Check out what happened below.