A Japanese pop star has been forced to cut off all her hair and make a tearful public apology after being caught spending the night with her boyfriend.

Minami Minegishi, 20, made the dramatic gesture after a tabloid magazine printed pictures of her leaving his house last week.

In an emotional four-minute YouTube video, now viewed almost 5million times, she asks for forgiveness and displays her shaven head, a traditional act of contrition in Japan.

A member of the popular girl band AKB48, Miss Minegishi explained she decided to cut off her long hair immediately after seeing the photos of her leaving 19-year-old Alan Shirahama’s house with her face hidden behind a surgical mask and a baseball cap.

The band has a strict policy that members should not be involved in any romantic or sexual relations and the group’s management agency demoted her to ‘trainee level’ yesterday, according to the band’s official blog.

She said she had been ‘thoughtless and immature’ and had considered quitting the group in shame.

‘I know this is being over‐optimistic, but I want to stay as Minegishi Minami of AKB48 if possible,’ she said. ‘It was all my fault about this. I am very sorry.’

She ends the video by saying: ‘As a senior member of the group, it is my responsibility to be a role model for younger members.’

Made up of girls in their teens and early twenties, AKB48 are one of the biggest musical acts in Japan and have sold millions of CDs and DVDs including an estimated £126million in sales in 2011 alone. (via)