Hilary Duff claims in court documents that she fears for her life, alleging she and her boyfriend are being stalked by two men -- one a paparazzi and the other a homeless man.

TMZ has obtained court documents, filed today in Los Angeles Superior Court, in which Duff and Good Charlotte frontman Joel Madden claim that a 19-year-old Russian emigre came to the United States "for the sole purpose of meeting and becoming romantically involved with Ms. Duff."

The court documents state the man, whose first name is Max, "admitted to being 'obsessed' with her, has stated his intention of 'removing' his 'enemies' (i.e., those who prevent him from being with her), has stated his intention of purchasing a weapon, and has threatened to kill himself and to engage in dramatic actions to get her attention."
According to the documents, Max "has stated his belief that Hilary is in love with him and that Joel Madden stands in their way."

The court documents also claim David Joseph Klein, a 50-year-old celebrity photographer who is roommates with Max, is also a threat.

The documents state, "Over the past six weeks, the defendants have engaged in an accelerated effort to make contact with Hilary, including visits to her neighborhood, to her mother's home, to her boyfriend's neighborhood ... to Mr. Madden's concert venue, and direct calls to Hilary's manager."

According to the documents, the police detained Max at least once at one of Madden's concerts and questioned Klein at the same event.

The stars are requesting a judge to order Max and David Joseph Klein to stay at least 100 yards away from Hilary Duff, her sister Haylie, Joel Madden and his twin brother Benji.