A young girl in China has apologised for "deceiving fans" for trying to join a boy band.

Fu Jiayuan, 13, said she lied about her gender to a popular management company because she was "young and ignorant".

Even though she was only part of YGN Youth Club's boot camp, and not an official band member, fans could watch her training videos on social media.

Ms Fu was forced to speak out after an internet user pointed out that she was in fact a girl.

YGN Youth Club only recruit young boys, most of whom are aged between 11 and 13. A challenging training programme trains them in song and dance and moulds them into future idols.

The company said the mistake had been made because auditions had been held online due to the pandemic.

"Our staff were negligent in the work process... In the future, we will adhere strictly to the company's rules and regulations," it said in a statement.

However, many on social media were amused by the revelation, and jokingly compared Ms Fu to the Chinese folk heroine Mulan.

According to legend, Mulan was a young woman who disguised herself as a man so that she could fight to save her family and country. The story is known globally after it was turned into a Disney film.

Some social media users said that the incident was "not a big deal".

"The look of idol groups is so androgynous these days, so it's hard to tell. Just let her join," a comment with one of the most likes said on microblogging platform Weibo.

But in her apology note which was posted earlier this week on Weibo, Ms Fu vowed to quit entertainment forever.

"I'm sorry to everyone who put their trust in me. I promise I will not show up in the entertainment industry or on any video platforms in the future," she said.

Companies like YGN Youth Club are widely sought after because families see it as a chance for their children to become rich and famous.

A study titled the "White paper on idol industry and fan economy in 2019" estimated that China's idol market would reach 100 billion Yuan ($15b; £11b) by 2020.

TFBoys, for example, which made their showbiz debut in 2013 when its members were 12 and 13, have since become household names.

But these management companies have been met with controversy, and criticised for taking advantage of young children for commercial use.

In recent months, China has intensified its crackdown on the entertainment industry and said it will ban what the national broadcaster described as "effeminate" styles and "vulgar influencers" in programmes.