By Mark Hosenball and Susan Heavey
WASHINGTON (Reuters) - The Obama administration on Thursday acknowledged that it is collecting a massive amount of telephone records from at least one carrier, reopening the debate over privacy even as it defended the practice as necessary to protect Americans against attack.
The admission comes after the Guardian newspaper published a secret court order related to the records of millions of Verizon Communications customers on its website on Wednesday.
A senior administration official said the court order pertains only to data such as a telephone number or the length of a call, and not the subscribers' identities or the content of the telephone calls.
Such information is "a critical tool in protecting the nation from terrorist threats to the United States," the official said, speaking on the condition of not being named.
"It allows counter terrorism personnel to discover whether known or suspected terrorists have been in contact with other persons who may be engaged in terrorist activities, particularly people located inside the United States," the official added.
The revelation raises fresh concerns about President Barack Obama's handling of privacy and free speech issues. His administration is already under fire for searching Associated Press journalists' calling records and the emails of a Fox television reporter as part of its inquiries into leaked government information.
It was not immediately clear whether the practice extends to other carriers.
The order released on Wednesday is from the U.S. Foreign Intelligence Surveillance Court and directs Verizon's Business Network Services Inc and Verizon Business Services units to hand over daily electronic data until July 19.