A federal judge in Greenbelt has sentenced a man to 15 years in federal prison for sending threatening letters to President Bush, a judge and a prosecutor in Montgomery County, and a Rockville attorney who uncovered the man's alleged embezzlement scheme more than 20 years ago.

U.S. District Judge Roger Titus handed down the sentence Monday for 52-year-old Scott Rendelman. The sentence was increased from less than 12 years after Titus learned Rendelman had sent threatening letters to two federal judges since his conviction in December.

Rendelman said the letters were his crusade against a justice system which he said allowed him to be raped and beaten in prison.

The death threats sent to the Montgomery County judge and prosecutor followed Rendelman's 2005 extortion conviction.