Here are five facts about Daniel Ellsberg:
Mr Ellsberg was born in Chicago on April 7, 1931 and was raised in the Michigan suburbs. He was a Marine Corps veteran with a Harvard doctorate. He had also worked for the Defense and State departments before reaching the Pentagon, as per the BBC.
Mr Ellsberg was a military analyst when he released thousands of documents to the media in the United States in the year 1971 that revealed that successive US administrations had lied to the public about the Vietnam War, as per AFP.
Due to the Pentagon Papers leak, he was dubbed "the most dangerous man in America", according to the BBC.
In 1971, Mr Ellsberg was accused of theft, espionage, conspiracy and other offences in a Los Angeles court. However, the court dismissed the case before the jury could make a decision, alleging substantial government wrongdoing, including unlawful wiretapping.
In February this year, he announced on Facebook that he had been diagnosed with pancreatic cancer and had six months to live.
Featured Video Of The Day
Daniel Ellsberg, Who Leaked Pentagon Papers Over Vietnam War, Dies At 92 Pentagon Papers Whistleblower Diagnosed With Terminal Cancer Vietnam War Pentagon Papers Whistleblower Wins Swedish Human Rights Prize Nurse Raped, Killed On Way Home, Body Found 9 Days Later In UP "Don't Expect Anything From Me": Kolkata Hospital's New Principal Loses Cool This US City Has Been Declared America's Least Desirable, Survey Finds Trump To Hold Press Conference, His Campaign Adds Senior Advisers Left, BJP, Creating Unrest: Mamata Banerjee On Midnight Attack At Hospital 'Don't Club Us With Others,' Says Manipur's Thadou Tribe, Waits For Peace Plan Track Latest News Live on NDTV.com and get news updates from India and around the world.