Washington, Jun 7 (IANS): Amid a furore over reports of a leading phone company sharing its records with the government, a media report said US intelligence agencies operated a much broader data-mining programme.

The programme extracted e-mail, photographs and other private communications from some of the biggest Internet companies, according to the Washington Post.

The agencies got access to the central servers of nine major firms, including Microsoft, Apple, Google, Yahoo and Facebook, the newspaper reported Thursday, citing a detailed briefing presentation document on the programme, called PRISM.

The programme has been running since 2007 and has undergone "exponential growth" since then, the Post reported.

It is now the leading source of raw material for the National Security Agency, the secretive US intelligence operation that monitors electronic communications.

The court-approved programme is focused on foreign communications traffic, which often flows through US servers even when sent from one overseas location to another, the Post said.

Between 2004 and 2007, Bush administration lawyers persuaded federal FISA (Foreign Intelligence Surveillance Act) judges to issue surveillance orders in a fundamentally new form.

Until then, the government had to show probable cause that a particular "target" and "facility" were both connected to terrorism or espionage.

In four new orders, which remain classified, the court defined massive data sets as "facilities" and agreed to occasionally certify that the government had reasonable procedures in place to minimise collection of "US persons" data without a warrant, the Post reported.

The Post said several companies contacted by it said they had no knowledge of the programme and responded only to individual requests for information.

The New York Times said a senior government official had confirmed the programme, but claimed it targeted only foreigners abroad.

Meanwhile, White House spokesman Josh Earnest defended the administration's programme of collecting the telephone records of tens of millions of Verizon customers in the US, calling it a "critical tool."

Speaking to reporters aboard Air Force One on Thursday, Earnest said that while he could not disclose classified information, the top-secret court order issued in April helped alert US officials to possible terrorist activities.