X Factor finalist Emily Nakanda has pulled out of the show after she was caught on video attacking another teenage girl.

The "happy slapping" mobile phone footage shows the 15-year-old holding the girl in a headlock and pulling her hair.

The victim, identified as Anna, is told: "If it rips out I'm gonna get blood on my clothes", according to reports.

It's reported she is shown in another video threatening to cut out a boy's eyes.

Judge Sharon Osbourne, who mentors Emily on the show, said: "I am deeply saddened by this whole situation."

A spokeswoman for the show said: "In response to the stories in the papers this week regarding Emily Nakanda, we have conducted our own investigations into the matter and we can confirm that she has chosen to withdraw herself from the competition with immediate effect."

Emily's mother Louis Friberg said the family is "very disappointed" with her daughter's behaviour.

"As a family we are heartbroken and are very disappointed with Emily's behaviour. We feel that there is no choice but to withdraw Emily from the competition.

"Emily and all the family sincerely apologise to both Anna, her school and all the fans that have supported Emily. Emily regrets her actions but there is no way, as a family, we can excuse her behaviour.

"Emily is very sorry to have let the show, Sharon and the viewers down."

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