English singer and songwriter Jessica Ellen Cornish is "scared for her own safety" after a fan broke her own legs and bombarded the singer with a string of disturbing letters.

According to a report in the Sun, the Jessica-mad teen claimed that she had broken her leg to look like Jessie and so she could wear a cast like the star.

It also reported that the teen (who cannot be identified for legal reasons) tracked down singer's private details and sent a picture of her shattered leg.

The fan sent the star with a number of disturbing messages, including: "I will do anything to be just like you."

Jessie J
Singer Jessie J performs with a broken foot on the fourth day of the Glastonbury Festival in Worthy Farm, Somerset June 25, 2011. Jessie J injured her left foot when she fell off a stage during a rehearsal a few weeks ago, according to media websites. REUTERS/Cathal McNaughton

"Jessie's a really, really sensitive and kind girl who loves keeping in touch with her fans. But this incident was just too much for her and she ended up getting really frightened and upset," the Sun quoted a source close to Jessie as saying.

"She was sad that a fan hurt herself to look like her - but she was also scared for her own safety."

During a rehearsal, Jessica, who is better known by her stage name Jessie J, broke her foot last at the Capital Radio Summertime Ball on June 12.

However, the 24-year-old singer performed the following day sitting on a gilded throne.