A former US intelligence worker has apparently gone into hiding a day after revealing himself as the source of leaked details of widespread US spying on private internet and phone records.

Edward Snowden, 29, was reported to have checked out of a Hong Kong hotel on Monday after the publication by the Guardian newspaper of an interview about his motives and actions. His whereabouts are now unknown.

In the interview, Snowden stated that he might be a target for extra-judicial abduction by the CIA, or the target of violence by one of the organisation's allies or third parties.

Snowden, who was working as a contractor for the National Security Agency (NSA) in Hawaii, travelled to Hong Kong after leaking details of the Prism spy programme, which harvests data from millions of private communications and phone calls.

The White House has said that an investigation is under way into the leak. It has, however, refused to discuss its scope.

Snowden's full interview has been watched by hundreds of thousands of people.

"I do not want to live in a world where everything I do and say is recorded," Snowden told the Guardian. "That is not something I am willing to support or live under."

'Defector'

US politicians on Monday reacted with fury to Snowden's actions.

Peter King, senior Republican on the House Homeland Security Committee, said: "I believe he should be prosecuted to the fullest extent of the law. I consider him right now to be a defector."

Dianne Feinstein, the Democrat head of the Senate Intelligence Committee, accused Snowden of committing an "act of treason" and demanded his prosecution.

President Barack Obama, the director of national intelligence James Clapper and other officials have insisted Prism has been authorised by Congress and is subject to strict supervision of a secret court.

US authorities face legal hurdles if they attempt to extradite Snowden. Hong Kong has a treaty but the document has some exceptions, including for crimes deemed political.

Snowden also told the Guardian that he may seek asylum in Iceland.

Snowden said in his interview that the public of the United States should decide whether Prism was justified.

A survey by Pew for the Washington Post, which along with the Guardian was contacted by Snowden, suggested that the majority of Americans - 56 percent - thought Prism was an acceptable way for the government to investigate terrorism. A substantial minority - 41 percent - said it was not.

The survey of 1,004 adults was conducted between June 6-9, with a 3.7 percent margin of error in the results.