The United States government is being engulfed by fresh accusations of widespread electronic surveillance of the American people.
It has already admitted to a secret court order it obtained to require Verizon, one of America's largest telecommunications companies, to turn over call records.
Now, more newspaper reports say its National Security Agency has operated a secret programme collecting data from some of the country's largest internet companies, Radio New Zealand's North American correspondent reports.
No sooner had President Barack Obama defended the US government's collection of data relating to millions of telephone calls made daily, than the newspaper allegations were published concerning a programme known as Prism.
Britain's Guardian and the Washington Post in the US published a 41-page previously classified presentation in which the NSA is claimed to be gathering data from Yahoo!, Microsoft, Skype, YouTube, AOL and others.
Internet firms deny giving government agents access to their servers.
The NSA is declining to comment about the Prism Programme, but fresh concerns are being raised in the US about civil liberties and adding to mounting pressure on the White House over the Obama administration's national security policy.
The papers say American intelligence agencies have been tapping directly into the servers of these internet companies in order to track individuals and the programme is said to have been operating for six years.
But James Clapper, the Director of National Intelligence, strongly defended government surveillance programmes. He said the disclosure of a secret court document on phone record collection threatened "irreversible harm" and revelations of an alleged programme to tap into servers of nine internet firms were "reprehensible".
The NSA confirmed that it had been secretly collecting millions of phone records. But Mr Clapper said the "unauthorized disclosure... threatens potentially long-lasting and irreversible harm to our ability to identify and respond to the many threats facing our nation", the BBC reports.
The article omitted "key information" about the use of the records "to prevent terrorist attacks and the numerous safeguards that protect privacy and civil liberties". He said reports about Prism contained "numerous inaccuracies". While admitting the government collected communications from internet firms, he said the policy only targets "non-US persons".
White House defends collecting records
The White House defended the collection of the phone records. Senior US Senator Dianne Feinstein on Thursday confirmed that the secret court order was a three-month renewal of an ongoing practice.
The order requires the Verizon to disclose to the National Security Agency the metadata of all calls it processes, both domestic and international, in which at least one party is in the US.
Such metadata includes telephone numbers, calling card numbers, the serial numbers of phones used and the time and duration of calls. It does not include the content of a call or the callers' addresses or financial information, the BBC reports.
US House intelligence committee chairman Mike Rogers said collecting Americans' phone records was legal, authorised by Congress and had not been abused by the Obama administration. He said it had prevented a significant attack on the US within the past few years but declined to offer more information.
Later, White House spokesman Josh Earnest described the practice as a critical tool enabling US authorities to monitor suspected terrorists.