Daniel Ellsberg, the leaker of the Pentagon Papers, has died. He was 92. 

Ellsberg's family on Friday announced his passing on social media.

In a letter posted on Ellsberg's Twitter page, the family wrote, "Today, Daniel Ellsberg died peacefully in his home in Kensington, California."

The family went on to reveal that Ellsberg's cause of death is pancreatic cancer. Ellsberg revealed his cancer diagnosis in a message that he posted to Twitter in early March.

He wrote:

I have difficult news to impart. On February 17, without much warning, I was diagnosed with inoperable pancreatic cancer on the basis of a CT scan and an MRI. (As is usual with pancreatic cancer --which has no early symtpoms --it was found while looking for something else, relatively  minor). I'm sorry to report to you that my doctors have given me three to six months to live. Of course, they emphasize that everyone's case is individual; it might be more, or less.

Ellsberg went on to reveal that he had decided to forego any kind of cancer treatment since it "offers no promise." Instead, he kept hospice care ready for when it is needed.

Ellsberg's family said that Ellsberg, when he died, "was not in pain, and was surrounded by loving family."

Ellsberg was a military analyst, and, as stated at the outset, he is most well known for the leaking of the Pentagon Papers.

For those unfamiliar with the Pentagon Papers leak, the Washington Examiner reports:

Ellsberg's leak of classified documents showed the true scale of the United States's involvement in Vietnam, revealing that multiple presidential administrations had lied to the public and Congress between 1946-1967. The papers, which he provided to the New York Times and Washington Post and were first published in 1971, showed the U.S.'s expansion of its actions in Vietnam without informing the public.

Subsequently, Ellsberg was charged with theft and conspiracy. He was also charged under the Espionage Act.

But, a mistrial ended up being declared after it was discovered that the government, under President Richard Nixon, had illegally gathered evidence against Ellsberg.

Ellsberg, thus, avoided what would likely have been a lengthy prison sentence.

Ellsberg, in March, reflected on the leaking of the Pentagon Papers.

He said:

When I copied the Pentagon Papers in 1969, I had every reason to think I would be spending the rest of my life behind bars. It was a fate I would gladly have accepted if it meant hastening the end of the Vietnam War, unlikely as that seemed (and was). Yet in the end that action — in ways I could not have foreseen, due to Nixon's illegal responses — did have an impact on shortening the war.