Johannesburg – The South African National Editors' Forum (Sanef) has strongly condemned the City of Cape Town's request for News24 to reveal its sources in a story about the metro. "What the City of Cape Town has done is totally unacceptable and must be condemned is the strongest possible way. I think it absolutely unacceptable that anybody would ask a media organisation or a journalist to reveal its sources," deputy chairperson of Sanef Katy Katopodis told News24 on Friday afternoon.This comes after the City's speaker, Dirk Smit, on Thursday requested News24 to disclose the source of a confidential investigation report into Mayor Patricia de Lille and other senior City staff.The request came after News24 published some of the findings of a report by attorneys Bowman Gilfillan this week. READ: City of Cape Town saga - Will De Lille survive the weekend?The independent investigation was commissioned by council after a series of damaging allegations against top City officials that started surfacing in September last year. Smit wrote in a letter to News24 editor Adriaan Basson that "no authority has been given for the release of the investigation report at this time".Protection of sources 'paramount in journalism'"I must request you to inform me who provided you with the confidential report and to refrain from publishing further information about its contents," Smit wrote. The report implicated De Lille, City manager Achmat Ebrahim and senior transport official Melissa Whitehead.The Bowman Gilfillan report found that De Lille advised Ebrahim not to report to the City council allegations of misconduct against Whitehead involving payments of more than R70m.Katopodis said the protection of sources was paramount in journalism. "If we were to reveal our sources every time someone asks us to, we wouldn't have any sources. People would be afraid to speak to the media about wrongdoings, because it would end up in witch-hunts, which could never be acceptable."On Sunday De Lille's fate will be decided by the DA's federal executive, after the party earlier asked her for reasons why she should not be fired.READ: DA Western Cape executive wants De Lille removedDe Lille has accused Western Cape DA leader Bonginkosi Madikizela of aiming to take over her job and is seeking legal advice on the Bowman Gilfillan report.