US spyware has its eyes on millions

Documents supplied by whistleblower Edward Snowden have revealed the existence of secret spy software that allows US investigators to search through databases containing e-mails, online chats and the browsing histories of millions of people.

British newspaper The Guardian reported on its website yesterday that the National Security Agency boasts that the program, called XKeyscore, is its ''widest-reaching'' internet intelligence-gathering system.

Yesterday, senior intelligence officials revealed classified documents to the US Senate judiciary committee in response to The Guardian's earlier stories on the bulk collection of phone records and internet surveillance.

In his first video interview, published by The Guardian on June 1, Snowden claimed: ''I, sitting at my desk, [could] wiretap anyone, from you or your accountant, to a federal judge or even the president, if I had a personal e-mail."

US officials strongly denied this claim.

Mike Rogers, the Republican chairman of the house intelligence committee, said: ''He's lying. It's impossible for him to do what he was saying he could do.''

But, said The Guardian, training materials for XKeyscore detail how analysts can use it and other systems ''to mine enormous agency databases by filling in a simple on-screen form giving only a broad justification for the search".

It added: "The request is not reviewed by a court or any National Security Agency personnel before it is processed.''

Much of what is contained in the declassified documents has already been divulged in public hearings by intelligence officials as they sought to detail what was initially disclosed by Snowden.

Intelligence officials have said the programs helped thwart terrorist attacks, but lawmakers have called for greater oversight of vast surveillance programmes, which expanded rapidly after the September 11 attacks on the US in 2001.

Snowden's passport has been revoked and he has been charged under the US Espionage Act.