Jack Anderson, the crusading journalist who tackled powerful figures like J. Edgar Hoover and won a Pulitzer prize for his reporting on the Nixon administration, died on Saturday at age 83.

Complications from a 19-year battle with Parkinson’s disease were the cause of death, his son Randy Anderson said in a brief telephone interview.

Anderson was hired by Drew Pearson in 1947 to work as a staffer on the column Pearson had founded, the Washington Merry-Go-Round, and later took it over after Pearson’s death in 1969. He only gave up the column at age 81 in July 2004, too ill to continue it as Parkinson’s disease took its toll.

Anderson is considered one of the major figures in modern investigative journalism, fearless in pursuit of a story. He won his Pulitzer for reporting on secret American policy decision-making that implied the United States leaned toward Pakistan in its 1971 war with India.

Former FBI chief J. Edgar Hoover and Anderson feuded for years over Anderson’s columns that indicated organized crime was a greater threat than Hoover had recognized.

Anderson also made it onto the former Nixon administration’s “enemies list.” G. Gordon Liddy, the Watergate conspirator, once said that he and other White House operatives discussed at the time how to stop Anderson including through slipping him drugs though no action was taken.

Anderson was born in Long Beach, California, to a Mormon family and grew up in Salt Lake City. He served two years as a missionary before launching his career at a local newspaper and then moving on to the Salt Lake Tribune in 1940.