Britney Spears Receiving Death Threats?

Britney Spears is fearing for her life after receiving a string of threatening phone calls and letters from an anonymous stalker, it's claimed.

The pop princess is said to be a nervous wreck following the alleged threats - which have also prompted concerns for the safety of her sons Jayden James and Sean Preston.

According to British reports, the fact that her boys may be at risk has sent the singer - who suffered a breakdown in 2007 - back over the edge.

A source tells Look, "Britney received some anonymous death threats over the phone and in the mail, and her worst fear is a kidnap plot against Sean or Jayden.

"She's been having terrible nightmares ever since then and she wakes up in the middle of the night crying out for her boys.

"She told her head of security and he thinks it's a lone stalker. Her paranoia has reached fever pitch and she's wracked with fear."

The source adds, "Britney is under so much strain, what with relentless performing, the bad reviews and the worry over her boys.

"It all got too much and she screamed at her team, 'I can't do this any more, why are you all torturing me?' She ran out of the room crying."

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