"Deep Throat," who helped bring down Nixon, dead at 95

The source, W Mark Felt, was a top FBI official who confirmed the reporting by Washington Post reporters Bob Woodward and Carl Bernstein on the Watergate affair.

 Felt's daughter and grandson confirmed Felt's death, which happened Thursday, to the newspapers. Daughter Joan Felt told the Post he died at a hospice near his home in Santa Rosa, California.

 The Watergate scandal involved political dirty tricks to undo Nixon's opponents and resulted in Nixon's resigning as president as he faced impeachment and removal from office by Congress.

 Woodward unmasked Felt's identity in 2005, ending one of the biggest and best kept secrets in US politics that had intrigued historians and politicians for three decades.

 Felt even had kept the secret from his family until 2002 when a friend told his daughter about it, Felt told the magazine Vanity Fair in 2005.

 The Watergate scandal erupted when Woodward and Bernstein, two young reporters chasing a routine police story, followed the trail of a June 1972 burglary at the Democratic Party headquarters in Washington's Watergate building.

 After Nixon's November 1972 re-election, knowledge of the break-in was increasingly traced to the Republican White House. As pressure for impeachment grew in the US Congress, Nixon in August 1974 became the first and only US president to resign.

 Coverage of the scandal put the Post on the world's media map and brought a new generation of young journalists flooding into the profession.

 The Washington Post's revelations of the Nixon administration's lying and "dirty tricks" against political foes deeply shocked Americans and added to a mood of national upheaval while the United States was extricating itself from the Vietnam War.

 Felt was nicknamed "Deep Throat" by Woodward and Bernstein for internal office discussions about the story. They took the name from a soft pornography film running at the time.

 He would meet the reporters in the shadows of a city parking facility, advising them to "follow the money" and confirming their research.

 The Post's stories were initially dismissed by big papers like the New York Times as the overhyped work of two lowly police reporters. But in the end, everyone had to pay attention as Congress opened an investigation and unravelled many of the details of the skulduggery in live televised hearings - a rarity in those days.

 The revelations held Americans spellbound in front of their television sets if they had one. Many went out to purchase their first set so they could follow the news.

 Some of those involved in the dirty tricks went to prison, including G Gordon Liddy, the chief operative for the White House secret unit, who spent four and a half years in prison for his role in the burglary.

 The story was later turned into an Oscar-winning film, "All the President's Men," based on Woodward and Bernstein's book and staring Robert Redford as Woodward and Dustin Hoffman as Bernstein.