Yahoo�s Launch reports that Bono has tighten his personal security after receiving thirty-four letters at his management company in Ireland. The threatening letters reportedly were postmarked in London, and Bono began receiving them two years ago. 

The letter writer takes issue with Bono�s philanthropic efforts to aid Africa by eliminating debt, fight famine and the spread of AIDS on the continent.  

The letters have now reportedly taken on a threatening form. The Sunday Mirror quotes one letter with the following, �You have been warned and you and your do-gooder friends had better watch out. ---- the foreigners and help your own people� If this carries on you will end up in a box.�

The threatening letters have been reported to British authorities and Scotland Yard and the Royal Mail service are reportedly conducting an investigation that is said to include examining the letters for DNA and fingerprints.  

Death threats apparently won�t stop Bono. The Sunday Mirror quotes a reported friend of the U2 frontman as saying, �He is a key player in the campaign to end Third World debt, and will not be silenced by death threats.�
 

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