A second US telecoms company accused of handing over details of its customers' calls to the government has denied the charges publicly for the first time.
BellSouth has now denied that it helped to create a huge database that is being mined for patterns of illegal behaviour.
"As a result of media reports that BellSouth provided massive amounts of customer calling information under a contract with the NSA, the company conducted an internal review to determine the facts," BellSouth said in a statement.
"Based on our review to date, we have confirmed that no such contract exists and we have not provided bulk customer calling records to the NSA."
Verizon's statement is more cagy. It states that until four months ago none of its business units handed over any information to the NSA, but it did acknowledge the database programme.
"Verizon cannot and will not confirm or deny whether it has any relationship to the classified NSA programme," it said.
"Verizon always stands ready, however, to help protect the country from terrorist attack. We also have a duty, that we have always fulfilled, to protect the privacy of our customers. The two are not in conflict."
The firm went on to say that at no point was data on domestic local calls in the US recorded and passed over. Such data is seldom even recorded, it said, since local calls are free.
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