THE NATIONAL Intelligence Agency (NIA) has lodged a complaint with the press ombudsman against the Mail & Guardian over a "false and defamatory" article about the agency's alleged leaking of tapes of tapped phone conversations to ANC president Jacob Zuma's lawyers.

But the paper is standing by its story, saying it is "very confident in the range of sources" that supplied the information.

Days after fraud and corruption charges against Zuma were dropped, based on intercepted phone calls "proving" a conspiracy behind the timing of Zuma's charging, the newspaper ran an article headlined "The spy who saved Zuma".

It said three independent sources confirmed that the tapes were leaked to Zuma's defence team by NIA deputy head Arthur Fraser.

Fraser has denied that he was the leak, and Zuma's lawyer, Michael Hulley, has denied that he received the tapes from Fraser.

Parker and Khan Inc, attorneys for the NIA and Fraser, said the paper ignored the fact that NIA spokeswoman Lorna Daniels had denied Fraser's involvement. "Your reckless, unlawful and defamatory publication has further seriously compromised the integrity of the institute which our client represents," the letter of demand noted.

Mail & Guardian editor Nic Dawes said yesterday that on top of the original three sources, the information had been confirmed by a fourth source. He said Fraser had been offered the right of reply, but had not taken this up.