Lady Gaga has increased her security amid fears she may suffer the same fate as John Lennon, it's been reported.

The former Beatle, who would have turned 70 last weekend, was shot dead outside his New York home in 1980.

Lady Gaga has apparently become paranoid after fans began sending her “ominous” letters.

“Some of her fans are completely obsessed - they make weird comments like saying they won't be happy until they die with her,” a source told Heat.

"She worries over how John Lennon died and fears the same happening to her. She has these horrible thoughts that there may be plans to kill her.”

Meanwhile, Lady Gaga is set to embark on the latest European leg of her Monster Ball world tour tonight (October 13) in Helsinki, Finland.

The singer, who returns to the UK in December, will release her new album 'Born This Way' in the new year.

(by Jason Gregory)