U.S. telecommunications operator Verizon has been required to hand over phone records of millions of its customers to the U.S. National Security Agency under a secret court order issued in April, according to a report by The Guardian.

Citing a copy of the court order it has obtained, the Guardian reports that Verizon has been ordered to give the NSA information on an “ongoing, daily basis” for all telephone calls within the US and between the US and other countries. Contents of conversations won’t be submitted, but information on numbers of both parties, location data, call duration, unique identifiers, and the time and duration of all calls will be handed over.

The secret Foreign Intelligence Surveillance Court reportedly granted the order to the FBI on April 25, which gives the US government unlimited authority to secure the data for a three-month period ending July 19.

The Guardian said it has sought comment from the NSA, White House and the Department of Justice for comment, but all declined comment. Verizon also declined comment, as required under the court order. Verizon is reportedly barred from disclosing the existence of the FBI’s request for its customers’ records, or the court order itself.

It isn’t known whether Verizon is the only telecoms provider to be issued with such an order, though the Guardian noted that previous reporting has hinted at the NSA collecting phone records from all major mobile networks.

This latest revelation will likely raise privacy concerns and could ignite a heated debate over the extent of domestic spying under the Obama administration.

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