A federal prosecutor found dead with 36 stab wounds last year was troubled about his job security and his boss's management style, according to a letter written by a colleague.

In a sharply critical letter to her boss, Assistant U.S. Attorney Lisa Griffin disputed that Jonathan P. Luna (search) was secure in his job in Baltimore.

"Jonathan is also gone after much heartache and distress over your style," Griffin, an 18-year veteran of the Maryland office, wrote to U.S. Attorney Thomas DiBiagio (search) in the Aug. 6 letter, which was obtained by The Washington Post and published Tuesday.

Just days after Luna's death, DiBiagio denied to The (Baltimore) Sun that Luna had fallen out of favor with his superiors.

"I am deeply embarrassed to hear that you led the press to believe that Jonathan was not in jeopardy of losing his job. That was not so," Griffin wrote.

Luna was so concerned that he hired an attorney to represent him on job issues, Baltimore's WBAL-TV reported Tuesday. Sources told the station that Luna believed DiBiagio was trying to push him out.

Luna, 38, was found face-down in a creek near Lancaster, Pa., on Dec. 4. He had been stabbed 36 times with what was believed to be a penknife and was left to drown. His car was found idling nearby.

In March, authorities said they were considering that Luna may have committed suicide. They also said they were exploring whether Luna could have been the victim of premeditated murder or a random killing.

Griffin's comments were part of a wide-ranging critique of DiBiagio as she wrote to inform him she was leaving Baltimore for a job at the Justice Department (search).

She wrote that DiBiagio was trying to create "a dangerous homogeneity of thought" in the office. "Good lawyers no longer speak up for fear of having their reputations tarnished," she wrote.

DiBiagio's spokeswoman, Vickie LeDuc, said DiBiagio called a meeting of his staff of 70 lawyers to review Griffin's complaints.

At the meeting, Griffin "expressed her regret for sending the letter" and her appreciation of DiBiagio's "commitment to address any and all concerns raised by the assistants in the office," LeDuc told The Washington Post.

She also told the newspaper that DiBiagio's supervisory staff reviewed Griffin's letter and found it had "no merit." She declined to elaborate when reached by The Associated Press on Tuesday.

Griffin did not return calls seeking comment Tuesday. She declined to comment to The Post.

Last month, DiBiagio was reprimanded in a rare rebuke from the Justice Department for urging his staff to produce three "front page" indictments of elected officials by the first week of November.

Deputy U.S. Attorney General James Comey (search) ordered the prosecutor to submit any proposed indictments in public-corruption cases to him.